CommentStreams:7fe99836aa3c0e1b44b503171f1e86bf

I'm pretty sure the primary factor is when in the day you first log in. My original account is maybe six months older than my main one, but they generally get sorted into the same tournament only if I log on to both within a few minutes.

There might be a more sophisticated algorithm for distributing players more evenly once your group is mostly filled--I definitely notice that after you have 60 or 70 people your bracket fills in much more slowly, and logging in with my alt account usually sends him to a different group. However, the first people in definitely seem to be all the folks who logged in around the same time.