I can honestly day that I haven't.   In my early days here,  I would watch someone back if they watched me as I thought it was polite to do so.   I don't do that anymore nowadays as it has lead me to having too many dead watchers.   I now only watch people if they meet two qualifications.   If their art inspires me or peaks my interest, and also if they have a nice, or at least an approachable personality, determined through basic conversation.   An artist's manner is just about as important as their works to me.

Sadly these days, I've been doing more unwatching than watching.  Either because they are no longer active,  or have changed personality wise to such a manner that I really don't care to converse with them any longer in addition to them no longer creating arts that get my attention.