DeeDubb
Veteran
Good point. But technically you don't need M for second block, you could do a more cfop style block
Also, as an example, if I were solving my blocks with white on bottom, the UL and UR pieces would be connected to their respective center, which would be yellow. Then the second block would basically be 2 F2L cases and 1 "cross" piece. It's truly not much harder than a typical second block, just a little less efficient.
Then you might as well do CFOP. The point of using M slices is that you don't need rotations, or F/B moves.
Also good Roux solvers can influence their UL and UR edges during EO, meaning preserving them after Step 1 is pretty irrelevant. Also, some CMLL algs take advantage pf the free M Slice, so you'd have to use less efficient CMLL algs.
