Yeah, some good players become feeders every once inawhile... you should at least give them the benefit of the doubt until they've done the same thing in 2-3 games.
Bad things happen sometimes. 
eg: I want to try a build with torch bearer... oh look it's Lordi17's cloak of the night oak... 7 deaths later and I can imagine my team mate it ready to strangle me.
It went something like this.
"Fireball!" (oak shield)
"hmmm... Ring if Fi..." (penitence interrupt)
Umm.... "Run!"
Warps in and puts his axe in the back of my head.
Well shit.
Guy had the patience of Yoda.
"Dude, you need to do something about your build man"
"I'm not a TB usually, sorry for learning what not to do on your time."
There's also the "Bro, you really need to lock the ports end game when you are playing Dominate on Zig"
You look at your inventory and see a lock, then look back on your desk to the 6 empty supecans. Do you fess up?
Hell no... "Sorry, my mistake man, I cost us the game but I will learn."
