I find this to be relevant
http://www.youtube.com/watch?v=ML2NjOUQgUw (skip to 2:38)
AP shaco is fine for trolling normal games, you can put up a lot of boxes and get an easy kill, but that's pretty much it.
AD shaco is really good early game, but completely useless late game.
Well yeah, I guess. I've just never seen a successful AP shaco in competitive play. He will get denied early game so he doesn't get any farm and he will be so squishy late game that he will only get one dagger off and he's dead. :/ I love playing him, but only to troll, because it really doesn't pay off in ranked games.
hes a ganker + assassin not a laner, if your team has solo laner go with him and when you can always go gank the other 2 lanes - thats your job as Shaco!