Part of it is a flip side of hiding comment scores. I think it's helped, but it also means that horrible comments that are too young to have been modded down yet are just as prominent as comments that the community agrees with. (If not more, due to the comment-order-semi-randomizer.)

One thing I have noticed in that vein is that it's impossible to tell whether a particular thread of comments is representative of a commonly held viewpoint, or if it's one commenter with an axe to grind. And if it's one commenter, they may have an entirely valid axe to grind! And then, even if it is valid, that axe may be totally off-topic for the post and dominate the conversation, retreading tired old ground and sucking up all the air in the room for interesting, relevant, new conversation. (Collapsable threading helps a lot though.)