I just tried it using my strangely tall coffee table instead of a chair, and I was actually able to do it! My chair is between 16 and 18 inches high. My coffee table is more like 20.
I guess even just attempting the move yesterday was engaging the right muscles, because when I just now practiced them on the table, I could feel exactly which muscles I worked yesterday--deep, deep in that little old glute... (not really so little, actually.)
Wendy