David Marek posted a link for a online books that goes into more details about rapid multiplication (originally posted by Cortona). Basically you let the tuber to form sprouts/shallow planting and then use the emerging plants as cuttings by rooting them. See some of that info here:
http://tomatoville.com/showthread.php?t=14199&page=5
Without rooting hormone I had 50% sucess on plants surviving forming roots and all.
The pulling is completely new to me as well so I go by experimenting...