In any game, after a few seconds of inactivity from the opponent, a link "This player is not playing, what can I do?" appears at the top of the play area.
It has been a while since I've had an opponent run out of time, but I believe as soon as someone goes into negative time a button appears to all players with a positive clock allowing them to expel the player who is out of time.
The F.A.Q. specifically mentions how the time system works, and that it is a player action to expel players who are out of time.
In order to run into negative time your opponent had to have at least a few episodes of slow play where you could have clicked the "what can I do?" link. Reading the F.A.Q. would have alerted you that you would have to take an action. It is not an "unfair advantage against new users" if those users do not learn the rules of the site, any more than it is an unfair advantage against new players to a game if you've read the rule book and they haven't. The rules are available and apply to everyone, so they are therefore fair. (Actually, the first time you play a game, your time is increased. It is therefore unfair biased
towards the new player...)
However, if you want to try the strategy of taking more time than negotiated against new users, feel free. The system does automatically decrease a user's reputation for each occurrence of a negative clock or table disconnect. I hope the few wins will be worth the reputation loss.
BGA was developed with the idea that playing games should be fun. As such, playing a complete game is more important than tallying wins and losses. An automatic loss the instant a clock goes negative is against this philosophy.
