The math is correct, however your "fix" isnt.
Unless you think that near 10% of your damage is shit, then you might aswell say that all of your spells are shit.
- - - Updated - - -
Dont think there was anything really, perhaps we'd gain more dps by forcing Stellar Flare use at the center now that its damage was nerfed.
Also treants shouldnt be the best pick of talents, either Inc or SotF (inc has really poor priorities in the list)