This worked for my DS
I didn't use a doll, just talked to him about it. When he had an accident and we practiced going to the potty, we started from different areas of the house and went through all the motions (turn on light, pull down pants, sit on potty, pull up pants, turn off light, etc.) each time.
DS was #1 trained in one day (2 accidents, I think). It took about a month for him to do #2 though...I think he was too tense sitting down and he just had to learn how to relax.
Emerson - happy, far-from-perfect, Christian, not-so-crunchy wife to K(3/05) and momma to M(11/06), S(2/08), and N(1/12)