If you disconnected from match, just forget about reconnecting.

My computer overheated & it self-shutdowns, and despite that, I still tried to turn back on & get back to the game as fast as possible. Even when I reconnected, I managed to catch up, assisted my team in grabbing kills, I even contributed in getting Baron as a team. And even though we still lost in the end 10-15 minutes after I reconnected, I'm still awarded 0 XP for all my hard effort.

So am I now inclined to believe that if you DC just one time, just don't reconnect ever?