# Most optimal way to find and handle Fridrich F2L pairs (Intuitive)



## xXdaveXsuperstarXx (Jun 7, 2009)

So, when I'm solving F2L, finding the Edge and Corner is very important. But what you must understand, is that once you have the cubies located, you have to pair them up. I have found that it is easiest to look for a corner on top and then find it's edge. This is not the best for look-ahead, but when the corner is on top you have a relatively easy case to execute and pair. Granted I always go for easy corner and edge pairs, but when there are no easy ones to spot I resort to this. Now for me it's also helped to do one pair and then do the slot next to it, instead of have to fill two slots diagonal from each other. You can see I plan out my F2L very carefully. I want to know what you think.


----------



## EmersonHerrmann (Jun 8, 2009)

Why can't you just look for the pieces and solve them as you go? Why waste time on planning?

P.S. - I do not look for a corner then an edge or vice-versa, I just look for the pieces...


----------



## xXdaveXsuperstarXx (Jun 8, 2009)

This is mainly for execution, and people who are dexterous. As I said, I'm a "2-Gen F2L kind of guy" So to speak.


----------



## cmhardw (Jun 8, 2009)

Now that I think about it I'm pretty sure that if I haven't spotted any pieces yet that I *usually* look for the corner first, then try to spot the edge. I don't do this every single time, if I see an edge first then I'll try to find the corner that goes with it. However, I think I have a more "corner biased" style of trying to look ahead than I do "edge biased" - I'm not a 50-50 split I guess I am trying to say.

Chris


----------



## xXdaveXsuperstarXx (Jun 8, 2009)

Okay, I'll just agree wich cmhardw because he can say it more simply.


----------



## JLarsen (Jun 8, 2009)

Just a counterpoint, you've stated your method, now how good does it actually work out for you? Or otherwise stated more bluntly, what's your average?


----------



## kjcellist (Jun 8, 2009)

I also agree with cmhardw. I almost always look for a corner first and then find the edge that goes along with it.


----------



## cmhardw (Jun 8, 2009)

Sn3kyPandaMan said:


> Just a counterpoint, you've stated your method, now how good does it actually work out for you? Or otherwise stated more bluntly, what's your average?



I average about 15.5 for 3x3. Here are some thoughts comparing Corner Bias to Edge Bias.

*Viewability:*
When looking for the corner first you can see at most 12 of the 24 corner stickers (assuming you view the cube slightly at a diagonal). This is 1/2 of the possible stickers a corner be in place of, or 50% sticker viewability. Assume here that we have solved the cross, and have not yet solved any F2L slot.

For edges you can see at most 10 of the 16 possible stickers, viewing at a diagonal, where an unsolved edge could be. This is 62.5% sticker viewability.

Before I classify the edge bias as better than corner bias now let's look at how many of those stickers determine which piece you have.

Corners:
Of the 12 visible stickers, 1 corner has all 3 stickers viewable, and 3 corners have 2 stickers viewable (allowing you to determine which corner you have). This means that you can correctly identify 4 of the 8 corners at a glance without a cube rotation.

Edges:
Of the 10 visible stickers, 3 edges have both stickers visible, and 4 edges have 1 sticker visible. Notice that I am ignoring the cross edges, if that was not clear already. This means that at any given time you can correctly identify 3 of the 8 unsolved edges.

From a "piece" standpoint I would say that Corner Bias is better because you can identify 4/8 pieces or 50% of the pieces at any given moment. For Edge Bias you can identify 3/8 unsolved edges or 37.5% identifiable at any given moment. Of course I mean here identifiable without a cube rotation.

----

Now consider when you have solved the first corner edge pair at FR. If you view the FR slot as being right in front of you, with the cube on a diagonal, then you now can identify 3 corners of the 7 unsolved, and 2 edges of the 7 unsolved. This places the corner visibility higher than the edges for identifying pieces. For sticker visibility for corners there are 10/21 visibility or 10 stickers visible of the total 21 unsolved stickers. This is 47.6% sticker visibility. For edges there are 8/14 visibility or 8 of the 14 unsolved stickers are visible or 57.1% sticker visibility.

Sticker visibility seems to prefer Edge Bias, but visibility taking into account ability to identify pieces without a cube rotation prefers Corner Bias.

I would say, in my opinion, that I would prefer to be able to identify pieces without rotating, thus Corner Bias, than to see more of the remaining unsolved stickers when using Edge Bias. So in short, I think the visibility argument shows that "Corner Bias" lookahead is better if you prefer ability to identify pieces without a cube rotation. Maybe some experts use Edge Bias, and can argue an advantage over seeing more stickers? The downside here is that you must rotate more to identify pieces.

I will try to look into the number of stickers visible by not just looking at a side of the cube in the static sense, but looking at the cube through the flow of a 90 degree cube rotation of either y or y'. This would be something that all solvers do, and is very important to lookahead as well.

This post is already very long, so I'll stop here though and post the rest later.

Chris


----------



## xXdaveXsuperstarXx (Jun 8, 2009)

I average about 25-27 sec.


----------



## deco122392 (Jun 8, 2009)

A general key for what I do (in cfop) solves to make f2l look ahead easier (rather identifying pieces) goes something like this:
Cor corners
-Look for sticker that matches cross colour.
For edges
-Any edge that doesn't have the colour opposite the cross.

That about sums up my look ahead in a nut shell. '
(of course I look at the adjacent stickers on the corners to know were to place them after i recognize that they belong in the first layer)


----------



## enigmahack (Jun 8, 2009)

cmhardw said:


> I average about 15.5 for 3x3. Here are some thoughts comparing Corner Bias to Edge Bias...



I appreciate the mathematics on this one... I've been having issues with my F2L being slow, and my whole average is hanging at 21 seconds, but I just can't break the barrier.

Anyway, I'm going to go home and see if I can adopt this somehow so that I'm corner biased so instead of getting lost on a pair, I'll instinctively look for a corner instead and go from there. 

We'll see how it goes


----------



## xXdaveXsuperstarXx (Jun 8, 2009)

Yeah, when you don't see any pairs laying around you should go right into making one instead of just looking two to be together.


----------



## deadalnix (Mar 16, 2011)

Nice post Chris !

However, I want to introduce some argument that will probably complexify the whole stuff.

First of all, edge determine if you can handle the F2L case in 2gen or not. Thus being edge biased allow you to spot easy F2L cases in a better way than corner does and avoid regrips. In addition, edges doesn't change orientation in most F2L manipulation, leading to no changement at all for edges in slot when you regrip, so you can keep them in ming easily. Corner can change orientation in such operation, leading to complex 3D thinking during the solve.

I tend to be easy to track pieces oriented. That means that I keep tracking pieces that are easy to track, and use them as a base to construct F2L pairs, combined with pieces in U layer ou frontal slots. This method allow me to be aware of piece that I actually don't see, thus improving my general nowledge of the current state of the cube.

Bests pieces to use as easy to track are correctly oriented edges in slot. Those keep correctly oriented if you regrip so you can use them as jockers, giving you an 2gen F2L in any situation. When you insert an F2L pair in this slot, then look for the corresponding corner, so you can have 2 F2L in 2gen.

Corners with U sticker on D are also easy. But usually lead to crappy F2L cases, so I prefers avoid using them, unless I have no other solution.

Correctly oriented edges on U are really easy to track. And as long as you have some of them, you know you can solve F2L in 2gen. 1 is potentially added with every F2L pairs inserted. Keep tracking them, they are crusial.

Do the same for corner on U. t seems like a lot of pieces, but actually most of them dont move during the solve. Pieces in slot don't move. Few pieces on U move during F2L insertion, and pieces on U keep being in U.


----------



## EricReese (Mar 17, 2011)

Not to sound mean or anything..but when you average 25-27 seconds..you aren't really justified in giving advicce on how to lookahead.

Great post though Chris  Now that I think about my solves, I notice I always search for a corner piece, though when scanning for one I do notice the edge pieces and that allowes me to sort of have a genearl idea of where to look for them later on


----------



## deadalnix (Mar 17, 2011)

Not to sound mean or anything, just considers what is written, not who is writting, you'll write less ****. And that's considering what is written, no who's writting.


----------



## Kirjava (Mar 17, 2011)

Wouldn't it be better to not have any bias? I know when I'm building the second block that I'm not looking for any specific type of piece. It's more like I'm looking for multiple pieces that fit together. When I see a piece that is part of the block I'll taken a mental note of it but won't start looking for pieces that connect to it - I'll keep looking until I see a group that fits together nicely. Sometimes this includes the first piece I came across, sometimes it doesn't. 

This might be harder to do in F2L as there are more places to look, but I don't have bias when I do F2L either.


----------



## qqwref (Mar 17, 2011)

deadalnix said:


> Not to sound mean or anything, just considers what is written, not who is writting, you'll write less ****.


Nah, sometimes the person who's writing is really important. If someone is trying to provide expert speedcubing advice of any kind, and they're not actually good at speedcubing, it means their advice is unlikely to be helpful. It still could be good advice, of course, but it's more likely that it would be misinformed and based on guesswork instead of experience. It's the same principle behind getting a sports coach: if you want to be good at football (for instance), you'd rather have someone who was once a top professional player, as opposed to someone who used to spend half an hour a week kicking a ball around with their friends.


----------



## deadalnix (Mar 17, 2011)

http://en.wikipedia.org/wiki/Argument_from_authority


----------



## FatBoyXPC (Mar 17, 2011)

qq: I disagree with that to an extent. Have you heard the statement: "Those who can't do, teach." I don't necessarily like that statement either. I agree that most people would rather have a coach that used to be a pro player, but you most certainly don't have to be a pro player to be a great coach. Being a good coach and a good player are different entities. While I can agree that being good at one can make being good at the other easier, but I don't think it must be that way.


----------



## RyanReese09 (Mar 17, 2011)

People who are pros know more then non pros. Tips and tricks are picked up along the way when you become a pro. It stands to reason (and I agree with qq) that I'd much rather have a fast(er) person (than me) giving me tips on how to get faster.

There is very very little (if at all) room for a slower person to give me tips, besides obvious flaws in my solving which I know about.


----------



## Kirjava (Mar 17, 2011)

I hate it when a thread drifts like this.


----------



## RyanReese09 (Mar 17, 2011)

Kirjava said:


> I hate it when a thread drifts like this.


 
<3


Spoiler











Except when


Spoiler


----------



## qqwref (Mar 17, 2011)

deadalnix said:


> http://en.wikipedia.org/wiki/Argument_from_authority


No, I'm familiar with that fallacy. Wikipedia itself says "[t]he fallacy only arises when it is claimed or implied that the authority is infallible in principle and can hence be exempted from criticism" and I am NOT saying that a fast person's advice is infallible. What I'm saying is that a slow person's advice about solve optimization is worse (in the sense of _less likely_ to be correct/useful), because most people who really understand it would be able to apply that knowledge to their own solves.



fatboyxpc said:


> you most certainly don't have to be a pro player to be a great coach. Being a good coach and a good player are different entities.


They're not the same group of people, for sure, because being a good coach requires teaching/coaching skills. That probably wasn't the best analogy. What I'm saying is that, if someone is slow at solving, it usually means that they don't have the personal experience to understand what is involved in being really good at it, and so they're probably going to be wrong about the best way to lookahead/fingertrick/inspect.


----------



## FatBoyXPC (Mar 17, 2011)

I agree with you, qq. I think I didn't quite word it the way I meant to, because I didn't want it to seem like I was being nitpicky about something.

I see people upload a video of an average and ask for tips and tricks to get faster, and I feel like even though I might be slower than them, I can easily help them with some things. Well, I guess that's not true. I guess ideally, if people were to ask for tips/tricks the "right" way, then I shouldn't be able to help them out at all. I can't count how many times I see people have pauses, fumble w/algs, etc. I think that if people were to research a bit more before posting those videos, those videos would be posted less.

I also often feel like people put too much weight in the "pro cubers." You have some people who know an incredible amount of cube theory, methods, algorithms, anything that helps cubes really, and some of those people aren't "that fast." To clarify, I mean somebody like Chris Hardwick, who doesn't have an official sub10 single, much less average. Don't get me wrong here, I'm not knockin' the guy, he's an awesome guy, and knows a lot (and is decently faster than me, even). The main reason he has so much credibly here is the fact he knows so much and been around for a long time. Sure he's great a blind, but blind and speedsolve require two different practices as well. Another great way to look at this is Mike Hughey. Great at blind, but hasn't quite got sub20 yet (officially, anyhow).

I guess my point is: I'd gladly at least try out any cuber's advice (if I haven't yet tried the same thing). Just because you aren't amazing at something doesn't mean that you don't understand how it works. While I agree that education and experience are different (and often present different mindsets), that doesn't mean that a less experienced but educated individual is not credible.


----------



## maggot (Mar 17, 2011)

on topic: 

i average around chris. 

i turn really slowly during f2l. what i try to do during f2l is look for either corners or edges. but what i will say, it is typically a corner. 

i am partial color neutral. sometimes during a long session where i am constantly going between 4 cross colors, it is hard to distinguish what is a good edge and what is a bad edge. it is incredibly easy to notice the cross color on the corner. this is the hardest part of being color neutral. people say the f2l is harder, but the reason why it is harder is because you arent typically following any edge, unless it is preceded by a corner. over time, i have become much more comfortable with making mental blocks when i switch cross colors. 

im having a really hard time trying to put into english, but to me 4 colors is just as hard as 2 colors. but 6 colors is awful! hahah

so, corner bias imho is the best way to be fast, because if you cannot distinguish where you are going with the solve quickly, you will have to pause in your f2l. it is easy to spot the cross color. it is harder to distinguish which pieces do not have the cross color or opposite color. more seasoned cubers will have slight edge bias, but i myself personally see good edges, but it means nothing until i see the pair. the best thing to do is to see the good edge and try to keep track of wether it is in an empty slot or in the top. that way if you do end up spotting the corner, you will know you have a pair.


----------



## EricReese (Mar 17, 2011)

deadalnix said:


> Not to sound mean or anything, just considers what is written, not who is writting, you'll write less ****. And that's considering what is written, no who's writting.


 
Um, when the person giving advice is around 30 seconds...no one will listen. The faster you are the more credible your cubing statements will be. That's a simple fact of life, there's no getting around it. Would you take advice from someone who is at 80 seconds on how to get faster at F2L? Well your answer would probably be yes just to spite me, but that's hardly the point.


----------



## cmhardw (Mar 17, 2011)

In regards to the comments about me, I always feel that my advice should be taken with a grain of salt. As far as 3x3x3 speedcubing goes, my average average is right at about 15.5 seconds. If you are looking for advice that will get you to 15.5 seconds on average, but possibly no faster, then taking my advice could be useful to you. If you're looking to be faster than that, my advice may create in you bad habits that do not permit you to improve much past 15.5 seconds.

Yes I maybe have been around a long time, but this could also mean that I have bad habits from the first generation and other second generation cubers that I am propagating, when in fact a completely different approach is much better for not only improving to 15.5 seconds but much further beyond that.


----------



## maggot (Mar 17, 2011)

EricReese said:


> Um, when the person giving advice is around 30 seconds...no one will listen. The faster you are the more credible your cubing statements will be. That's a simple fact of life, there's no getting around it. Would you take advice from someone who is at 80 seconds on how to get faster at F2L? Well your answer would probably be yes just to spite me, but that's hardly the point.



i think no matter how slow you are, the conversation is interesting enough. sometimes interesting things happen when you conversate. sometimes faster cubers are so stuck on what is successful for them. everyone has their own unique cubing style. even if you are slow, if you are intellegent you can sometimes give a fresh look on something that helps the community progress in some fashion. and along with this, sometimes just bouncing ideas around are the ways that new things are created. 

i think this thread is not about giving advice, they are just bouncing ideas around for what works for them. its up to you to judge wether you take their statement with a grain of salt. if it is their 3x3 avg, then so be it. dont read any of stachu's posts, because hes just a noob then.


----------



## RyanReese09 (Mar 17, 2011)

maggot said:


> i think this thread is not about giving advice, they are just bouncing ideas around for what works for them. its up to you to judge wether you take their statement with a grain of salt. if it is their 3x3 avg, then so be it. dont read any of stachu's posts, because hes just a noob then.


 
Statue averages 16. That's not all that bad.


----------



## Cool Frog (Mar 17, 2011)

RyanReese09 said:


> Statue averages 16. That's not all that bad.


 
What method =/


----------



## a small kitten (Mar 17, 2011)

Who does the world revolve around again?


----------



## hatter (Mar 18, 2011)

I think this is (hopefully) relevant..

Everyone always says "practice practice practice". I cannot seem to break the 20 second barrier (I've been here for about.. a year? Though, granted, I have a laundry list of things more important than cubing). I want/need to get better at F2L, mostly finding pairs as I think I can execute the insertion rather quickly.


How do you guys actually PRACTICE finding them? I feel like just repetitively doing f2l is somewhat helpful but it has no benefit over just repetitively solving the entire cube.


----------



## EricReese (Mar 18, 2011)

Fridrich he is 16 i know. however if stachu breaks sub 20 with L2L4 then Ryan has to learn it, that is what he promised IIRC.


----------



## qqwref (Mar 18, 2011)

fatboyxpc said:


> You have some people who know an incredible amount of cube theory, methods, algorithms, anything that helps cubes really, and some of those people aren't "that fast."


You seem to assume I draw the line at people who are very fast, but that's not true. Basically, I think everyone can get down under 20 seconds; if you are young (under 30 or so, let's say) you should be able to get down near the 15 second mark on average. This is with full Fridrich (or the equivalent) and some lookahead and fingertrick ability. Someone who's gotten down to that level probably understands optimization and lookahead tricks; someone who's still over 20 seconds probably doesn't, because they're still at the point where they have a lot of pauses in their solves. You definitely don't have to be down near Faz speed to have a full understanding of what it takes to be fast; in fact, I'd say that the biggest difference between someone with a global average of 13-14 seconds and someone with a global average of 8-9 seconds is turnspeed.

As for Mike Hughey - no offense to him, but I very much doubt he's an expert at speedsolving. However, he is definitely an expert at blindfold solving, and from his times/accomplishments I'd expect a lot of knowledge in that area. In the same vein as the speedsolving stuff, I generally wouldn't take BLD optimization advice from someone whose best time is in the 3-4 minute range or higher.


----------



## deadalnix (Mar 18, 2011)

hatter said:


> Everyone always says "practice practice practice". I cannot seem to break the 20 second barrier (I've been here for about.. a year? Though, granted, I have a laundry list of things more important than cubing). I want/need to get better at F2L, mostly finding pairs as I think I can execute the insertion rather quickly.
> 
> 
> How do you guys actually PRACTICE finding them? I feel like just repetitively doing f2l is somewhat helpful but it has no benefit over just repetitively solving the entire cube.


 
Try to make a pair, but do not insert it. Then look your cube to find the next pair. Close your eyes, insert the pair and prepare the next one. And continue.

However, as I'm not that fast, so this advice is complete crap. But knowing that kanneti does the same will change this crappy crap into golden crap. Maggically. I'm not sure excatly why yet, ask EricReese for more details about that particular point, he seems to know a lot about crap.


----------



## ilikecubing (Mar 18, 2011)

qqwref said:


> biggest difference between someone with a global average of 13-14 seconds and someone with a global average of 8-9 seconds is turnspeed.



Completely agree with that


----------



## a small kitten (Mar 18, 2011)

> However, as I'm not that fast, so this advice is complete crap. But knowing that kanneti does the same will change this crappy crap into golden crap. Maggically. I'm not sure excatly why yet, ask EricReese for more details about that particular point, he seems to know a lot about crap.



Chill. You are seriously overreacting. I'm pretty sure any sort of advice will be considered but advice coming from people with more reputation, experience or good competition results will most likely be considered first. After all, people get a lot of information thrown at them here. I don't blame them for being selective about who to listen to first. It takes time and motivation to work in a new technique. Being supported by somebody with experience and results is slightly more encouraging.


----------



## Escher (Mar 18, 2011)

I really don't see what's wrong with stating that faster people are more likely to have good advice...


----------



## cmhardw (Mar 18, 2011)

Escher said:


> I really don't see what's wrong with stating that faster people are more likely to have good advice...


 
I think the issue is not whether this statement is correct or not. I think most people would agree that this is true.

I think the issue is that people who feel they have something to contribute are afraid of being ignored if they are not "fast" or "fast enough". As an example, Richard Patterson has been my de facto cubing coach for years. He is pretty fast, but is not at faz speed or anything. Just because he is slower than faz doesn't mean that he can't still give excellent advice on how to improve (in speedcubing, fewest moves, blindfold, etc.)

Your first statement still allows for this by the way. It is more likely that someone who is faster will give better advice, but this means that slower people can also give good advice, and also fast people can still give bad advice (bad advice for some).

I hope that makes sense to others, as it does to me in my own crazy mind


----------



## ASH (Mar 18, 2011)

"most optimal" lol


----------



## maggot (Mar 18, 2011)

what i have to say about the comment. 

it was said in a fashion, who are you to give advice? you are slow. 

so basically we're telling our newer speedcubers not to post and only allow people who are sub 15 to give advice. that's stupid. when i was 'slow' (sup 20), i refrained more from giving advice. i would goto the noob threads and give advice. but seriously, i feel like i could have given advice to someone sub 20. maybe not all people do, but i've read so much material about getting faster, i could just repeat it and claim it as my own. not something i did from personal experience per say, but definately solid advice. if people would question my reputation, well, let them ponder about my skill level. if they ask, i will tell them. if they say, who are you to give advice? well, let me just get the link to the place where i read it. 

we cannot continue to bash noobs or 'slow' (sup 30ish) people because they typically have good intentions. where is common courtesy?


----------

