Several years ago, my colleagues and I attempted to get a small paper published, it was rejected and we ran out of time - and as it was a 'side-project' type of paper, we left it at that. We thought that was the end of it - this was not the case.
One of the reviewers who made themselves known to us wrote some pretty terse messages to us about his disagreement with what was a relatively minor point. We graciously took his feedback as he is an established (published) researcher in that field. We moved on to different fields - which this reviewer has no published work in.
What has been happening since is that he will write an email questioning every single paper that I get published, not deliberately being insulting - but not offering anything constructive nor asking for clarification of the content etc. He has admitted that what I research is beyond his area of expertise - examples of his questions are (remember, these papers are collaborative and peer reviewed):
"Are you sure you know how to use (equipment)?" - when the paper stated a previously published (by a separate author) protocol has been followed.
"Are you sure you did enough trials?" - this would be fine as criticism, except the next email stated "That many trials seems like overkill" referring to the same paper.
One particularly unhelpful comment from him was "Did you actually pass high school English?"
Criticism is fine, and is sought for any and all work that we do, but when the statements do not offer anything substantial, are contradictory or just rude - this is not criticism, it is unhelpful noise -especially when it is posted publicly where we display links to the work (he deletes his comments soon after most of the time)
How do I deal with this persistent 'academic stalking' while at the same time, not make a 'fuss'?