I'd be sorely dissapointed if a feature like this came into D/P because that would prove that the development team had suddenly decided to chuck game balance out of the window. Ahh...I can see it now.
Random tutor person: Lyk, hi an' stuffs. I'll teach your Sableye Miracle Guard, okay?
You know what? I'd really rather not. -.- Widen the range of potential traits for pokémon? Fine by me. But do you even realize how disruptive it would be if we suddenly got, say...a bunch of Snorlaxes with both Thick Fat and Immunity? Or Sheddy with some uber protection trait for a second? Kyogre with Torrent to add to its already overpowered damage potential? Where would be the fun in playing? xP
Reusable tutors I wouldn't mind, at least for some key-moves like Rock Slide, but the price should be something a bit more imaginative than just money, methinks. Something along the lines of the Battle Frontier BP system is a start, could also be like theFallarbor tutor who wants Heart Scales...but meh, just as long as it's not something ridiculous like trait tutoring. Seriously, traits are supposed to be the unique (Well, sort of. xP) abilities developed by the pokémon species in question over generation upon generation of gruelling evolution, and now you want some random dude to give them in five seconds? It makes absolutely no logical sense, not even in a world where living beings can be stored digitally.