Nah, I think if artists would just see the negative comments for what they are negative comments, it'd all be far less stressful. One should be able to properly discern the difference between a "flame" and a constructive criticism. ...
... If I submit something [like a wallpaper, pretty much all I *do* submit hehe...] and I'm confident in my submission, why would I care if some person comes along and slings around ungrounded negative comments? If I'm confident in my work, I don't care what kind of negative feedback I receive, because the only ones I pay attention to are that of the skinners themselves OR if someone wants something specific.
The only reason I think ungrounded comments should be removed is because it might give a bad impression on any newcomers to the site, or just a regular visitor. Comments containing slang, of course, should also be dealt with in the same manner. As forthe negative comment ITSELF, I don't mind any I just take a look at the source instead of letting them get to me.
..my point is, all of you skinners are consistently putting out good work, and ALL of you are still learning... try not to let what others say put a damper on you. If these "trolls" knew any better, they'd submit skins themselves..