Fix this problem
Don't fix this problem
Not a good idea, and i tell you why i dont think so. What if you get lagged out a game a couple of times in that time span (happens a lot). You wouldnt be able to game at all for hours. Then look at the posts on the forum..
See here's the big issue. I understand what you are saying, but yet I can't really agree with the solution. You see, people leave for numerous reasons whether it be server DC, real life related issues, getting Butthurt over the hundredth red bar warrior killing them with lightning hands through five walls or the constant red light district every single match you get in (aka all sniper teams). The problem is a ban thing will not solve anything, it may actually make things worse than they are (due to less players to match against in lobbies), nor will it keep people in matches. I can't really think of anything aside from Bungie making fights more like year one gameplay to try and help the issue, and even that may not solve anything, as people are continuing to be disenfranchised with this title everyday. So it's not a simple fix, and nothing that will keep players from leaving, ban or not.