I don't believe in giving a hitter extra credit for being the best hitter on his team, even if he's essentially the only hitter on his team and his team is really good. For the moment, then, let's just look at Gonzalez's case in a sort of vacuum ...
He was an excellent player from 2006 through 2008. Not a brilliant player, by any means; Gonzalez simply didn't get on base quite often enough for that. But in 2009, Gonzalez somehow changed his game. In 2007 and '08, he averaged 56 unintentional walks and 140 strikeouts per season. But in 2009, he drew 97 unintentional walks and struck out 109 times. Which made him one of the National League's three or four best hitters. And he's one of the league's three or four best hitters in 2010, too.
Does that mean he's a serious MVP candidate?
Well, only if you do give him credit for being the Padres' only productive hitter. As it happens, each of the other contending teams in the National League with one deserving Most Valuable Player candidate has two of them (or close). The Reds have Joey Votto and Scott Rolen. The Giants have Andres Torres and Aubrey Huff. The Cardinals have Albert Pujols and Matt Holliday.
Gonzalez probably is the best player on a good team who's carrying so much of the load by himself. I just don't think that's enough to push him past Votto or Pujols (or for that matter Ryan Zimmerman, who's not going to get any MVP attention but should). If Gonzalez were tied with those other first basemen? Maybe. But he's not.
Now, about Kirk Gibson in 1988 ... First, Gibson was really, really, really good that season. It wasn't really a hitters' year and Gibson didn't hit a lot of home runs. But he finished fourth in the league in OPS, second in runs scored, and first in Wins Above Replacement.
Still, as I'm sure you know, MVP voters in 1988 didn't spend a great deal of time thinking about OPS and WAR. They liked batting average and home runs and runs batted in, and Gibson didn't fare particularly well in any of those categories.
So the fact that he probably deserved to win doesn't really explain why he won.
Some of you remember why. Some of you don't, because you were six years old. Kirk Gibson won the Most Valuable Player Award in 1988 because in spring training he ripped his new Dodger teammates for their unprofessionalism. The media ate it up, the Dodgers won the division title, and Gibson also played well enough for the voters to justify supporting him.
But that part, you wouldn't know by just looking at the numbers. Most MVP and Cy Young winners, and Hall of Fame selections, can be "predicted" using statistical models. But some of them, the interesting ones, can't be. Which is why I believe the historical study of awards voting remains a rich vein for ambitious researchers.