Let's take an honest look at Smith.
Last year, he scored a decent 17.3 points per 36 minutes, and if that's all you look at, you give the Knicks a big "yeah" and move on. The problem is whatever time he plays and whatever shots he takes, he's going to be taking time and shots taken away from others.
Smith is a long way from an efficient scorer. He has a lifetime field-goal percentage of .428, and last year, he was just .435. That's not very good.
It might be acceptable if he were a great defensive player as well, but he's not. In fact, he's a below-average defensive player at best. Last year, he had an oPER of 16.2. He gave up an utterly horrendous 1.02 points per play, based on Synergy data.
He's a great team player though, right? Wrong again. He's got serious questions about his coachability. His basic moral judgment is in question. Even after literally killing a friend due to reckless driving, he has had two speeding tickets and had his license suspended three times.
George Karl had to bench him numerous times because he refuses to accept coaching. In the playoffs of '07, he took a 50-foot three-pointer with the game on the line, which wasn't the designed play (surprise!).
"I have no idea what planet that came from," Karl told the Associated Press. He had drawn up the play to give the ball to either Allen Iverson or Carmelo Anthony. Karl did not stop there and continued venting over Smith's poor play, "And then, of course the one with eight seconds to go, from 50 feet, I just love the dignity of the game being insulted right in front of me."
These problems aren't just old. They were still going on last year. They were going on in China. He's a horrible team player.
This warrants concern for a team that has found recent success because of defense and chemistry, as much as the splendid play of Jeremy Lin.
The Knicks need to be concerned. Smith will be taking less efficient shots than Amar'e Stoudemire, Carmelo Anthony or even Lin or Tyson Chandler. He'll be wanting to take more of them. He'll be sulking when he's not taking them, and to top it off, he'll be providing horrible defense on the side.
Anthony might be the concern for some right now, but he'll at least try. I'm not sure you can say the same about Smith.