Let's just make one thing clear:
When you are playing normals, and someone is playing something different, DON'T LOSE YOUR SH*T ABOUT IT.
I just played a game as ADC Urgot and already before the game even starts, my top laner starts pestering me about it. Then, every time we have a team fight and we lose it or I make a mistake, he goes to /allchat just to say that "gg botlane too heavy" even when our lane isn't to blame. Am I the best Urgot around? Of course not, but don't start pinning a loss solely on someone that is "playing something off meta". [slayer-jinx-unamused] I don't know anymore, I'm not sure if I'm more pissed off from the toxicity in these preseason games, or from my connection being really crappy.
Anyways, just give people a chance instead of just assuming they are gonna bomb the game.