The worst thing about nerds/geeks (regardless of whether they're gamers, roleplayers, tabletoppers, cardswappers, socceridiots etc. etc.) is the minority "hardcore" segment who simply takes themselves too seriously and believe that they have the answer to every single question that might possibly come up in their field.
Like when I play Warhammer 40k tabletop and air an new army concept I've been thinking about and this one guy goes: "Nooo, that won't work - wraithguards are simply to costly and with only toughness 6 they're... blablabla... you'll loose every single game."
Or I try out a build for my warlock in WoW and this guild-person goes: "Nooo are you insane! that won't give you the sheer dps needed for taking down , and doesn't even do good in Arene, what do you think you're doing?".
Well... to that question, only one answer: "I'm trying to have a bit of fun... (idiot)."