The match reporting page on the site makes use of a library called pyreplib to parse replays for players. This library gets the job done, but has serious downsides when compared to the much more mature repasm. One of those downsides is that the library does not distinguish between players and observers - so we assume that the two players with the highest APMs are most likely to be the players we are looking for.

This is a pretty good assumption... normally :)