Patrick's continued insistence that all stealth games are intrinsically bad (except for Mark of the Ninja). Yes, they have learning curves, just like every game, and those curves are often steeper than average for stealth games, but no decent stealth game relies on trial and error to solve every situation in the entire game. If the player is relying on trial and error throughout the entire game, then they are not thinking ahead or being patient at all.
Jeff's hate of Red Dead Redemption and Dark Souls, despite having played very little of either game. He insists up and down that those are both definitively bad games, despite having only played Dark Souls for half an hour and Red Dead for not more than that. It isn't that he holds those opinions that is annoying ( I would still disagree), it is that he presents it as the truth rather than an opinion based on very little experience with the game. There's a large difference between saying, "It didn't appeal to me early on and I don't want to go back to it. It just isn't for me." and saying "It's a bad game." As someone who is a veteran in the field of game reviewing, I would think that he should be able to tell the difference between first impressions and a full review and temper his opinions as such.