Earlier quoted context omitted.
Ironically, leaving a "thank you" will typically get deletions/nags from the self-appointed comment police. As much as I like (and heavily use) SO, it has a real problem with making people feel like shit when asking, answering and commenting. There are people who are exemplary in their politeness and helpfulness like the top-contributor, John Skeet. There are also quite "mean" people like Hans Passant (also super-hig…
Honestly, I am in the camp in favor of deleting "thank you" comments. I view the whole platform as a fantastic way to curate high-quality content for the whole web community. I don't come to Stack Overflow to socialize or make friends, I come because I'm trying to get my widget to work and I just want to find the solution to my problem. While expressing thanks is definitely an admirable human quality and should be la…
I agree that a comment consisting of nothing more than "thank you" isn't particularly helpful, but a "thank you" + some twist or application tip is interesting and valuable. Sadly, some SO-cops just see the words "thank you", ignore the rest of comment and then immediately recite the rules and/or delete the comment.
As for SO communicating the difference, I think they already do. Their problem is that people like me _deliberately_ ignore "the rules" and post whatever we think is appropriate-- the mods just can't keep up.