ok here is exactly why. BitComet reports false data to the tracker and to other peers. it reports that it is sending out way more data to peers than it actually is. so by banning it, and forcing the leechers to use clients that dont cheat, we get a healthier torrent. because (not sure if everyone knows) a healthy torrent works on the rewards system most of the time. meaning its like "ok ill send you a piece of this torrent, then you tell me when you sent it to someone else, and ill send you another." Bitcomet, as soon as it recieves a piece, weither it sends or not, reports back to the client that it recieved it from that it sent it to another peer. by removing the leechy client by nature, the torrent gets healthier, and the people who use real clients, and try to go 1:1 on the torrents get the complete torrent faster.