It is simpler in actually manipulating the cube to avoid moves that
use the back; in particular, the FFBB slice move is a difficult one to
actually do. So I would recommend BUB' and BU'B' at the ends of
a RRLL slice. In addition, if you define X = RL' (or R'L) followed by an
entire cube rotation (ie, move the slice and allow the orientation
to change - turn the ham, not the bread ) then the sequence becomes:
BUB' (UUXX)**2 BU'B'.
---- Stan
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