(naruto) so how can't lee use nin or gen?

Rock lee is supposed to only be able to use taijutsu. Although he can use the chakra control in his feet to climb walls and walk on water. In my opinion that is a ninjutsu itself. It's really the same concept as the rasengon just simpler. Even if that is not technically a ninjutsu being able to do that means he should be able to learn other jutsus. So what do you think? Am I right?