x, y, and z are simply variables, and can be substituted with 0, 1, -
1 ('), or 2 to fit your need...

For ex, in corner orientation, if you wanted to twist BLU corner
clockwise and FRU corner counter-clockwise, you first need to do U'
to place BLU in position 1 (FLU), do LD2L'F'D2F, then U2 to place FRU
in position 1 (FLU), do F'D2FLD2L', and finally U' to put all corners
in their original position.
So the whole algorithm would be:
U'-LD2L'F'D2F-U2-F'D2FLD2L'-U'
This is the case where x=-1, y=2, and z=-1.
One thing to notice is that x+y+z=0 for all corner pairs. Well, you
can of course figure out z by keeping track of any U corner piece. :D

If you want to twist corners on U and D layer, just do R2 or
something to get both corners on the same layer, rotate the corners
in the same way you would for corners on U layer, and then do the
inverse of whatever you did... in this case, R2.

All algorithms for blindfold cubing work this way...
1. Perform moves to place pieces you want to move in the spots where
you can use algorithms without screwing up the orientation.
2. Perform the algorithm.
3. Perform the inverse of whatever you did in 1.
Once you understand this and how orientation works, blindfold cubing
isn't too hard...

Hope that helps,
Macky

--- In speedsolvingrubikscube@yahoogroups.com, Kyle Bryant
<craptastic_crap@y...> wrote:
> what in the hell does Ux, Uy, and Uw mean in stiff
> hands' tutorial??? HELP!
> =-K-=
>
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