I'd like to delete my comments here on EL&U and leave my answers pristine as I go through them to make sure that I still agree with what I wrote here 2 years or so ago.
Is there a way to delete all my comments here?
For regular users there is no special tool to remove all comments. You'll have to go thru them all one by one. Or maybe there's some user script that can help simplify matters.
In case removal of your comments makes some of the rest of the comment threads end up obsolete, flag them for removal as well.
I hope you don't delete the ones that are useful for future visitors.
NVZ is the expert of meta, so I expect the system doesn't allow comment deletion en masse, though a software expert might be able to devise a special purpose script to serve your purpose.
May I only add that there seems to be a general consensus we should not delete our output all together but only those items that need deletion: in short, the user has discretion to delete individual comments one at a time, and can indeed manually delete thousands of comments one by one in a laborious manner, but your body of work contributed one question/ answer/ comment at a time is considered valuable by the community.