Am I too optimistic?

Xander knows the sign for potty. Per some parenting article I read, it was suggested to teach him the sign for potty while changing his diaper. The last few days, when he needs a diaper change, either because it's dirty or because it's opened up (stupid velcro closures), he signs potty. He still seems more interested in playing with his little potty rather than sitting on it, but it's a start. Right?