I actually was going to try this training with my then 3yr 1 month old after having no luck with what I was doing. He had no interest in going to the bathroom in the toilet. So instead of pushing the situation, I stopped talking to him about it for about 2 weeks. Then I started mentioning to him that I was going to buy him underwear and asked what kind he wanted, then I brought them home and Buzz Lightyear pullups (yes I did use pullups and it did NOT affect his training). What did it for him was he was standing in the bath tub and I caught him standing up peeing in the tub the way he should pee in the toilet, so I immediately took him and said, oh that is such a good job that is how you should go pee pee in the toilet and took him over there. He was so happy that I was excited and praising him, even though it wasn't in the toilet that time, he stood up to pee.
So I decided to stay home on a Friday and work with him, I actually bought him Buzz Lightyear Pullups for training, he loved them. The first thing that Friday morning when he woke up I asked, do you have to go potty, and he actually said yes, and went in the toilet. From then on, he has been going Pee and Poop in the toilet. (Trained in one day) I did not throw out the pullups as they did not affect the way i trained my son. He loved them, and didn't want to wear diapers anymore, he has only had maybe 2 accidents in a month now. He wore the pullups for the first week, now he is in underwear during the day and I still put Pullups on him at night, even though he hasn't had any accidents. I never forced him to go potty, everything was always positive, and praise, getting excited every time he went and then he was happy also. I never disciplined or forced him. Every child is obviously different, we tried for several weeks, cheerios, watching daddy etc, and finally I told him he will get a big present when he goes potty in the toilet. This was after we stopped talking about it for 2 weeks. I kept telling him that and he went and he got a big present. Try to stop talking about it for a week or 2 (as maybe he feels a little pressure, at 3 1/2 they want to do what they want to do not what we want :) ) and come back and ask him what kind of underwear he wants to wear and that he will get a special prize/present when he does go. I didn't end up needing to follow the Training by Lora Jensen because he did it so quick.
Good luck with your training :)