Normative statements in comments
It's really great the amount of feedback that people are giving in the comments. But, the comments feature may be more useful if users do not to have to sift through normative statements such as: "This doesn't make any sense." I just read the comments on a translation (33 comments total) and the majority of these comments were expressing basically the same thing. Maybe it would be useful to prompt the user before posting the comment with a question such as "does this help the discussion?" Or, maybe the upvoting could be revamped to highlight the most useful commentary. Another alternative would be to hide comments from certain users. I'm not trying to discourage people from engaging socially. But, excess chatter really diminishes the usefulness of this feature.
The upvoting system moves the most upvoted comments to the top of the page. The downvoted ones go to the bottom, and after a rating of -3 or so, they become hidden. Unhelpful comments are deleted by moderators at their own discretion.
I delete as many as possible as I hate the clutter, the trolling, and the "LOL" comments. If there is an intelligent comment/question about the sentence or the language etc..., and it turns into a related discussion that may include a "LOL" comment, I'll usually let it slide. If a comment is downvoted and hidden because it is wrong, I won't delete the comment. Most of the time it has been replied to with a correct solution and it could be helpful to anyone reading the comments that might have thought similarly.
I don't know how other moderators handle non-helpful or off topic comments. I don't know how many moderators frequent the Spanish section. Maybe they haven't come across the discussion(s) you're talking about, or maybe there are fewer moderators frequenting the Spanish section (I really don't know how many there are or how "evenly spaced" they may be).
If you want, you can post a link to the discussion here and I'll have a look and see if I can do anything.
Hope that helps!
I think the solution is for everyone to be more active in downvoting useless comments, and upvoting useful ones. As Hohenems said, low-scoring comments will get moved to the bottom, and very low-scoring ones will be hidden. Initially I didn't downvote much because I thought it might be seen as rude, but honestly it's not a judgement on the commenter -- just on the comment.