BAR uses dedicated OS ratings rather than in-game scores for matchmaking balance. The official website explains this design decision in a guide page that covers the reasoning behind the system.
Tags: beyond all reason, rating system, lobby balance, matchmaking
Using raw in-game statistics for matchmaking creates exploitable patterns. Players could farm easy matches to inflate scores. Dedicated rating systems track wins, losses, and opposition quality to produce more reliable skill measurements.
The BAR website hosts a complete guide explaining the rating system and lobby balance at beyondallreason.info slash guide slash rating-and-lobby-balance.