Join in progress, though a decent idea in itself, becomes more of an annoyance than a benefit when you realize that no one joining a game in progress EVER wins. Why? Because the games that people leave (creating spaces to fill) are almost always already significantly unbalanced. I would rather NOT have extra team mates in an already unbalanced fight than lose every match that I join in progress. Solution? Get rid of JIP, increase penalty for leaving early.