Thanks for that Q alg. It's a lot easier to remember and much quicker to executeOne reason I push M2 from the very start is I think some people just getting started will get a few successes with OP edges and stick with it for a while because it's what they know and M2 isn't that much harder, just different.
For Q btw, I suggest (U' M')x3 (U' M) (U' M')x4 or (U M')x3 (U M) (U M')x4, whichever direction is most comfortable for your finger tricks. A lot of older references suggest (B' R B U R2 U') (M2) (U R2 U' B' R' B) which is intuitive but not very execution friendly IMO.
I was wondering if there was some golden number given any number of corner swaps or rotations. I'll try your method on L and R, it does seem more efficient than trying to trace all the edges. ThanksI track edges I've traced on the L or R faces with my fingers and simply try to remember any I've hit on the M slice. The competent 3bld folks just develop a natural sense of when the trace is done. I tried using a checksum instead of fingers early on but I don't think it's a fruitful approach, at least not for me.