The law of averages is not ok.
Just for the devs and people who trawl the boards looking for comments:
The law of averages is not an acceptable solution to ranked game AFK's.
It would be better if a team mate goes afk for more than 7.5 minutes, that loss prevention goes into effect, the game is nullified for winners and losers in terms of LP gains, and a notice (like the remake notice) pops up and says that the match can be FF'd without loss.
In terms of long term game health for the community, it is a QOL improvement that should not be overlooked.
