EDIT [4/21/14]: I'm bumping this to the top for our new moderators.
Possible duplicate of this question, but I see the problem persists, so let this be a friendly reminder.
Although the comment box clearly states
avoid comments like "thanks", "+1", "me too", I see these comments are much more common in this site than on others.
Surely many of us have been guilty of this in the past, myself included, but come is it really necessary to state your agreement every time you see a good answer? That's what upvotes are for.
I'd like to appeal to the community, please restrain yourselves. These comments do not add value, and may even obscure others that do.
Finally, as this answer suggests, can we be more aggressive flagging non-constructive comments while at the same time avoid making them? What else could be done in order to get the point across? For example on SO the comment What have you tried? is being explicitly blocked, would it be wise to do the same? (yes that measure does sound more authoritarian than it should be, just to give an example)