For clarity, the purpose of the change was to address the issue that Grav Round, on its own, was responsible for too much of your overall DPS. In other words, using totally made up numbers, if all you did was mindlessly spam Grav Round, you could still achieve something like 85% (again, totally made up) of your total damage dealing potential.
Not only was it bad, it wasn't fun (for the target or the caster). When things are bad, not fun, and yet they're still effective, they become high profile candidates for tweaking.
What we did was lower Grav Round's damage and increase Demo Round's damage. I don't know what the net result is off the top of my head, but we feel it's much, much closer to a "rebalance" than an outright "nerf."
And in case you're worried, if it turns out to be more of a nerf than a rebalance (which we don't want to be the case), then we'll fix it. But even then that'll probably be in ways that don't directly affect the damage dealt by Grav Round.
Grav Round places an armor debuff on target.
Grav round charges barels for higher High Impact Bolt damage.
Grav Round increases Commando's survavibility by adding shield stack.
Grav Round increases Demolition Round damage by adding gravity vortexes.
Grav Round procs Curtain of Fire.
It has no cooldown.
It is a tech ability so it bypasses defenses.
It's relatively cheap.
It has relatively short cast time.
With all respect, even if you cut Grav Round damage by half, people would still spam it due to numerous buffs it provides.