I'm not sure if you're mistaken or just disregarding a horrible parity case.I do that in a different way than I do on 3x3 though. I usually do it by looking at blocks. For example, if there is a CEC block, I know that there cannot be another block (except for a j perm) for it not to have parity.
Have you ever heard of the "three-color rule"?Dene said:For example, I have particular trouble distinguishing E perm from what I will call "E parity"; I have to line up the edges to make sure it is one or the other.
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