well with the abwheel i go all the way out and let my stomach touch the floor but not my arms this makes for a crazy tricep burn in the higher reps
first set ill get 15-20 ill lay on the floor and bust out another 10 lay and rest and just keep knockin out 6-10 till i get about 50-60 or so
I hate doing ab work really. I'm somewhat of a lazy trainer.
When I force myself to do it I'll try something like what you're describing.
Since...abs are critical as far as aesthetics go.
Good to hear from someone displaying real results. : )