Movie matchup bug?

This isn't so noticeable ranking all movies, but when you drill down to say, only movies you have seen from 2009, where there may only be 20 movies for the site to match up, it does an awful job of picking films to match up. I ranked maybe 100 different matchup and the same 7 or so films were the only ones ever to be in a matchup. Generally the highest ranked few and the last ranked film are chosen.

This became abundantly clear when I ranked films only from the 40's. I've only seen 4 films from the decade. Flick chart only gave me the same matchup for all 15 times I tried (my #1 and #2), it would not include my #3 or #4. This is a major bug.