The Facts Behind "Games Behind"
Games ahead/behind has nothing to do with baseball standings. In fact, it is possible for a team to be a half game "ahead" of another and be in second place.
Case in Point: I have before me a book called The Baseball Catalog. In it there is a example from early in the 1978 season where 8-5 Mets were a half game "ahead" of the 5-3 Phillies, but the Phillies were in first place due to a higher winning percentage (.625 to .615)
The discrepancy between the number of games played had something to do with this, as with the current one between the Sox and Tigers. Like the current one, it was no doubt weather induced. But as author Robert creamer said of a similar discrepancy in his book Baseball in '41 games behind is "and artificial stat, with no official weight."