Aha! I have success! Last night I executed my first ever forethought heel with a magic cast on. This means I have live stitches on the heel, plus live stitches on the tube of the leg, ready to knit when I finish grafting the heel.
I will attempt more picture plus a better explanation later. That is, if the pics are good, I will try to explain. Trying to explain to Ember already failed miserably.