I don't think so, we generally don't use the watch function. My teammate was covering for me during a leave spell, and she joined the board and commented on the cards. Since i have returned she has left the board, but is still getting notifications regarding the card activity.
@Ben Maas if she is still a member of a team, and has watched any of the cards (which she will have by default because of that stupid checkbox Trello added in recently) then she will still get notified. You can remove her from the team to fix the problem. I think if you remove her from the team and she loses access to all those boards, then you re-add her it should "reset" the situation and she won't get those notifications any more.
If you had to thrive a new habit during a lockdown, what would it be? Trello
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