I quit trying to Dispel the Negative Recourse a while back with the 'Shadow Heals' line after had some folks tell me that it was dropping the positive heal effect on them?
Pseudo tested on Pet a few times that was low health; I could see the big bumps in his HP every tick while the spell was doing it's 4 ticks. If I did the Cancel Magic on myself it seems the big ticks stopped for him as well; mirroring the behavior of what the other players were telling me. (Yes, performed this before the spell naturally wore out)
I presumed this was 'fixed' a while back to link the target-caster effects and to cancel one would cancel the other. Can't prove -- didn't try any further. Now I just don't fret it. Less hassle trying to juggle buffs and don't feel 'dirty' for 'exploiting' the unintended. Shrug.
YMMV and hope it works as expected for you.
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