Tighty cartoon-ighties

So, we are sort of talking about potty training w/C and moving into a big boy toddler bed (well converting his crib into the toddler feature).  He likes to go pee on the pottie about 5 times a week--no pooping though, and he doesn't seem to understand the big boy bed question.  So as incentive for potty training, we showed him his groovy undies.  He was pumped.  He immediately wanted to try them on.  So we let him.

This turned in to him putting on 3 pairs at once.  He wanted one of each kind--Thomas, Nick toons, and Elmo.  It was really funny.  He just kept grabbing them and saying more. 

We told him he couldn't wear them again until he tells us he needs to go potty.  He can recite this requirement to you, but it hasn't done a thing toward giving him the desire to stop playing to go potty.