Colin Dunlap has a good point about the Pirates' recent run at contention, and what might have happened if the Pirates' front office and many of their fans had already had their way and moved the team to the NL East:
↵↵↵Where are all the people now who, after the PHI series, wanted #Pirates in NLEast? This pennant chase is too much fun, stay in NLCentral.
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Right. The Pirates would be nine and a half games back if they were playing in the NL East. In the NL Central, they're one game back. The presence of the Phillies would be great for the Pirates from the standpoint of selling tickets - none of the Pirates' rivalries with NL Central teams are anywhere near that level - but bad in terms of their actually being able to contend. And I think that pattern would likely persist in the future as well. In addition to the Phillies, there's also the Braves, who are typically run pretty well (and would also have left the Bucs in the dust by this point). I'll take the Cardinals, Brewers and Reds over those two franchises any day.