Short answer:
No.
Long answer:
I’ve seen a lot of talk recently about Buster Posey and his AFL performance. If you didn’t know, Posey is hitting .230/.338/.361 in 61 at-bats. Most of the discussion seems to center around his current batting line and how it either represents that Posey isn’t ready for full-time MLB play or that it means that Posey doesn’t have enough endurance to play the catcher position.
Let’s tackle the first idea that Posey isn’t ready for full-time MLB play because of his hitting.
The fact is that trying to draw any conclusion from 61 at-bats is the definition of small sample size. Consider this, a full-time player can get between 90-100 at-bats in a single month. To judge Posey on 61 at-bats would be like judging a hitter based on less than a full month of baseball. It’s less than 10% of a full season of baseball. It’s just too small to draw any grand conclusions from. Hitting in the AFL (or in any short season winter league) shouldn’t be a barometer of success. Running through the list of some of the AFL hitting leaders (by OPS) from previous seasons is a weird mix of good talent and not-so-good talent. In 2005 Yankee prospect Eric Duncan led the AFL with an OPS of 1.157. Four seasons later he seems to have hit his ceiling as a AAA player. In 2006 Kevin Frandsen was 2nd in the league for OPS with a score of 1.068. The Kevin Frandsen story hasn’t panned out quite as well as the ’06 AFL would have led us to believe. In 2007 Sam Fuld led the league with an OPS of 1.118. The list goes on but the point remains, weird stuff can happen in small samples. Of course, you’ve got some good performances from prospects that went on to make something of themselves, but how well a player does in the AFL doesn’t seem predictive of anything. Instead of looking at just 60-something-odd AB’s, we should look at Posey’s entire excellent year.
Secondly, because Posey isn’t a league leader in hitting, he might not have the endurance to play catcher.
This premise might bug me the most. I think we can all agree that the catcher position is one of the most physically demanding positions on the baseball diamond. A lot of scouts (Keith Law, Sickels, etc.) have noted that Posey has looked tired in the AFL. Can we really blame him? He’s been playing baseball since April 9th when the San Jose Giants season started. Posey has been playing baseball for at least 8 months. Maybe even more if you consider his preseason routine. Even Joe Mauer would be physically exhausted at this point. There’s no shame in being a tired catcher at this time of year. And, unless we’re training Posey for a 10 month baseball season, I would consider his year a wild success.
We would all love to see Posey tearing up the AFL but don’t get worked up about 61 AB’s. He’s had a very successful year and should be the starting catcher for the Giants at some point in 2010.

I just hope all this work isn’t having a permanent negative affect on Posey. It seems (obviously I can’t say for sure) that Suck It Russell Martin was worn into the ground and went from a great offensive catcher to blah. Or maybe his deal with Satan just ran out.
Couldn’t agree more. People also forget that he has only been a full time catcher for a few years now after not starting out there at FSU.
People need to be prepared to see him struggle in 2010 as he faces better pitching and gets used to the big league game, but his talent is evident and in the long run I think the Giants are going to be rewarded with one of the best backstops in baseball.