Yeah, at the same time I think that people closing down every review as "clearly biased" isn't particularly healthy too.
Most of my friends weren't massively impressed with Deadpool - mostly because it was so universally praised that I think they thought it'd be the second coming of comedy and superhero movies. By the time I saw it, I really enjoyed it, in big part because my expectations had been lowered by my friends disappointments.
A lot of my disapointment form my original TFW viewing was for similar reasons.
Completely writing off any negative feedback entirely will only lead to people being disapointed if the move's a just a good movie, and not an epicly amazing movie.
My dislike of Snyder is well known, so I'm not too keen on the Watchmen comparisons. I won't agree with the reviewer who had written it off pre-view though, more because of Afflecks involvement than anything. He's actually got a lot of experience at acting, writing, producing, and probably as much directing experience as Snyder. We already know he's re-written a lot of parts - he has so much professionally resting on this film that I think he wouldn't settle for making another Daredevil.