Well, that's certainly a concern, but the plan is to have some sort of formula that takes into account the different ranking levels of the players involved, so if you eliminate a new or low ranked player a whole bunch, that's not going to help your ranking, and if you let a low-ranked friend eliminate you a whole bunch, then that's going to drop your own ranking down. If you're both at the same rank and go eliminating each other back and forth, then you'll just stay at around the same rank.