Problems with AFK

I'm sure most of you have faced a situation where your teammate does not reconnect or he/she reconnects and disconnects continuously. I personally feel that this becomes a huge problem when someone is playing in a rank, especially when he or she is in a promotion. I understand that this is also a very difficult problem to solve, mainly because there seems to so many ways we can abuse the system if we are given some kind of solution to it. For example, if a team with a afk for more than 5 or more minutes is given a loss prevented, every time our team "seems" to be losing, we can force one player to afk for more than 5 minutes to ensure that the whole team gets a "loss prevented". However, I feel that the way around this is to punish those who had gone afk, much more than the current punishment. AFK for more than 5 minutes, a few days ban. Seems harsh, but I feel that is a sort of harsh measure to stop people from abusing the system, if accepted.

What are your thoughts?