I have heard about a technique for centers in 4x4x4: before remembering them you should check if you can do a slice so more centers will be on their positions. Does anybody use this trick? What should I do with edges on that slice? Should I remember them as they are already in new positions? Or there is an algo that fixes them back?
I have never heard of this 'technique' but I can tell you that it's most likely worse than not doing it. There is[/i] a technique that should always be used, where you rotate the cube's orientation to solve as many centres as possible. You don't have to do any extra algs to fix things and it can solve a lot of centres. It can be used on 6x6 without any issues too. It also can be used on 5x5 and 7x7 but you have less orientations to choose from because you need to be able to solve the middle centre pieces with something like M E M' E' or M E2 M' E2