I guess the part I don't understand is why the hell you think Shaco doesn't requires skills.
You do realize that Shaco is one of, if not the squishiest champion in the game right? Makes sense since he has a flash every 9 seconds with invisibility, but that still requires a good amount of knowledge and intuition to use correctly (Do you use it to get in, or do you use it to get out? Etc.).
That alone by virtue requires that the player be skilled in using him, you need to absolutely think about when you go for a target since you will get blown up.
I hate to be that type of dude, but yes the above posters are correct, you've clearly have never played or even tested Shaco out before if you think the only part of his kit that requires skills is his clone.
He's fine the way he is; strong early game, weak late game, weak team fight, strong split pushing. He has his clear strengths and weaknesses, no need to toy around with it.
A good Shaco is probably one of the most frustrating things to play against, rightfully so since he has such a high skill cap.