Idea on Dealing With AFKs, Specifically in Promos

So, we're all aware that Riot is hesitant on implementing a system that prevents LP loss/unfair LP gains as a result of a player or more leaving a match for long periods of time or the entire match itself. The reason is because players can and will attempt to abuse a system like that.

My suggestion, for all its worth (nothing), is that when an ally is disconnected from the game for a minimum of 5 minutes between the 3 and 15 minute mark, the team is allowed to surrender the match with a majority vote.

The match will not be counted as a loss for the losing side, but the losing players will have LP deducted from them as though it was a loss.

What this system would accomplish is allow players who are in their promos a more fair means of completing their promos successfully in the event of an AFK.