Most people don't realize this, but this is what makes healer +dmg actually significant. In a 5v5 with say a tri-healer team, your team can still do 4-5k+ instant burst to finish a target off. That will affect games and lineups alot more than the fact that a 1v1 with a dps vs a healer won't be automatic win for the dps anymore.

Even if it's the "killing blow", it's still insignificant compared to how damage affects a real damage caster and healing affects a healing class. Situations like that just don't happen randomly. Nudging the margin of a killing blow a bit forward is a minor change.

Exactly what glickz said. The only difference you might see is that healers that didn't help nuke for killing bursts already may start to do so. The good healers already do this when appropriate, and it's very effective. I have 583 spell damage on the PTR, 483 more than I have on live, with a 6.43% crit chance. The difference between my mind blast+death now and on the PTR is 414 more damage, going from 1432 average to 1846 average, a 28.9% increase in my burst (42.9% coefficient on both Shadow Word: Death and Mind Blast).

414 more damage isn't earth-shattering when we're talking about targets with 11k health and 400ish resilience. Healers assisting burst is nothing new, and healers have been using clicky damage trinkets to help burst people down for ages. You're thinking its bigger than it is because in your mind its going from 0 to 1846, not 1432 to 1846 because most people aren't situationally aware enough to juggle burst damage on top of their cooldowns/healing/dodging interrupts/LOSing CC/dispelling/offensive purging/mana burning/shocking/judging/HOJing/cycloning/shifting/etc.