[Pelican]

I suspect that you would find a greater correlation, if you looked not at the entire season, but the record for the last month (excluding games after clinching playoff position). It's a long season. Teams with impressive records can head into the playoffs with injuries, or in a slump. And teams that barely score a Wild Card berth can be on a roll. I would expect that a team's performance in recent weeks going into the playoffs would be a better predictor of playoff performance. And good teams (see Phillies, Philadelphia) know how to hit another gear in the post-season, even against teams (see Braves, Atlanta) with much better regular season records.