I did answer there, and I just realized it was a bit stupid and not what you asked for... So I copy my answer here:
I do not think the pinging will add to more heated conflicts, because of faster interaction. But maybe the notifications will make you more stressed, to enter the watchlist is more of an active action. I dont go into my watchlist everyday, so I do miss a lot of replies which maybe is good for the discussion climate, but it was not the intention when adding the page to the watchlist.
A simple technical solution could be: Instead of notify in "My notifications" have the notifications in the watchlist instead. That will make the change from "adding a page to the watchlist" a bit smaller as it is "add a thread to the watchlist".
Actually, adding the subscription to the watchlist was what I excpected when the feature was presented to me.