I think x2/y is the best colour neutrality for speedsolving petrus, because with full colour neutrality you have to choose between three different ways of expanding the 2x2x3 during the solve, and I don't think there is time for that when you're solving for speed. I find that it is hard enough to choose between two when using x2/y. x2/y is also enough to allow you to start on all 8 2x2x2 blocks, the same as full CN. -Tao Yu
I agree here, I feel that the eo inspect would be more difficult aswell.
(Im also x2/y cn)
’I think people who don’t go for full CN in a method which needs full CN are just lazy’ - PetrusQuber.
Just joking.
x2/y means you start on either white or yellow and expand around any block, just not up, right?
Disadvantages: Depending on what 2x2x1 you choose and it’s relativity to the W/Y layer, you’ll have to get used to 3 different types of last edge. I always just put the 2x2x1 in the bottom, and inserted the last edge with a variety of moves. Having to start on one axis means there are 3 possible ways to insert the last edge and swing in the 2x2x1, which doesn’t give any advantage. I guess you could just get used to it, but something to think about.
Well... What if the entire 2x2x3 block was solved after 2x2x2, but for the top layer? Can’t use it then can you? I know it’s hard to look at all 3 options as you come from 2x2x2, and I generally just go with the BRD block, but you should still be able to recognise significant advantages like a free pair, or the other expansions being bad.
I’ve never found any problem with EO recognition, and it’s the same kind of thing as:
Don’t be colour neutral with CFOP, there are more options and things to get used to so it’s bad.
I also occasionally switch between an R and U layer block if the U layer is exceptionally good - no doing that with x2/y