Lol. Look, I'll try to explain this slowly. Shawn Marion has a really weird shot, but the release point is the generally always the same. Regardless, most of his scoring was done by using his elite athleticism and shooting wide open jumpers. Barbosa also used his elite speed to do most of his scoring. The problem with MKG is his release point, which is different on almost every shot because he double clutches. I'm not acting like he won't be able to score, but if you think he's ever going to score 18 ppg then you're in for a pretty big shock. I've already detailed the reasons why he won't ever be an average scorer in the NBA, but hell...I'll lay down a bet.
If MKG ever averaged 18/7/4/2, I'll pay you $500. You don't even need to offer me anything, that's how positive I am that he will never have a season like that.