Basically, a fandom (or at least a faction of it) who is so stuck in their beliefs in their work of fiction of choice, canon or fanon, that they will even disregard Word of God
from the creator of the piece itself.
An example would be that there was an interview between Pokebeach.com and a storyboard artist from the Pokemon anime: the storyboard artist gave several explainations about several things that the fandom of the anime has nagged about for years (The GS ball: a Macguffin that was later forgotten about, and Misty's departure and the chances of her appearing again.)
However, fans were decidedly not happy at all with his answers. They then made claims that his answers didn't count because he was only a storyboard artist and not a writer on the show. Some even went as far as to launch personal attacks. Such as calling him a sexist pig.
Not sure if this is even viable trope though.