As I earlier posted, I’ve been learning OLLs and PLLs at a moderate pace, trying to move past the inefficiencies of the Beginner’s Method. About half-way through learning A Perm, a light bulb went off: It corner cycles the same way as the penultimate Beginner’s Method algorithm of R’ F R’ B2 R F’ R’ B2 R2 — with Aa as the far less re-grippy surrogate, and Ab (its mirror) more efficient than serial application of the Beginner’s Method algorithm. (Slowly, it’s all coming together….)

I find the A Perm one of the easier cases to recognize, with its characteristic 2x2x1 block in a top-layer corner, the block having matching colors on either side. I set up by AUF‘ing the 2x2x1 block into the front-left corner, with the 2×2 block matching the middle and bottom layers (as in the diagram to the right). If the headlights (green-xx-green in the below diagrams) are in the back, you do the Aa Perm; if the headlights are to the right, you do the Ab Perm.

A Perm (Corner Cycle)
Aa PLL(CLOCKWISE) (Lw’ U R’) D2(R U’ R’) D2 (R Lw)	Ab PLL(COUNTER-CLOCKWISE) (Lw’ R’) D2 (R U R’) D2 (R U’ Lw)

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