Can we have a search term to discover comments by a particular user? I've tried a few permutations without success.
Something along the lines of:
No. There isn't, and there should not be.
SO is about Questions and Answers, not comments. There has been a constant squeeze on comment-related features and it should stay that way.
Anything with URLs is just light weight hack-ish.
Who are you trying to stalk, anyway?
Yep, and you already know how to do it. :) Replace
Now, of course, this shows a list of questions where you have comments -- so if you need something more granular, yes, you need the data dump or the sandbox.