Interleague Play and the Prime Directive

There's been a fair amount of concern, justified in my opinion, that a disparity in interleague matchups could wind up being determinative as far as who makes the playoffs. For example, the Mets get the Yankees six times while the Marlins face the Devil Rays as their "rival." More relevant for my concerns, the Marlins get the Indians while the Phils have this now-concluding series against the Twins as their non-common opponents... and those games where they face the Devil Dogs, we have three against the Orioles and three against the Red Sox.

But so far this doesn't look like it's been a problem. Put aside the weird tendency of the NL East teams to march in near-lockstep--for the last two weeks or so, it's seemed like the Phils and Marlins win or lose in tandem almost every single day--it also looks like we're all pretty much treading water in these series. The Phils thus far are 2-2 in interleague; I think the Marlins are 2-3, as are the Braves. I don't think this has had much impact in the Twins-White Sox race either. It's almost enough to make me think MLB has secretly implemented a Prime Directive of non-intervention in the other league's races... which, really, would be both more fair and more interesting.