It says on the skill that high SP means higher damage reduction. I wonder how low could a High Wizard or even better, a Scholar reduce an Asura to with this.
The damage reductions are based off of your current sp compared to your max SP so increasing you max SP size will not effect it. 90% of total SP will still provide the same damage reduction whether you have 9 sp out of 10 or 900,000 out of 1,000,000.
Any class can find a use for this class remember this card isn't catered to our server so other people wouldn't be spamming GJ...
I was mostly thinking about how it will be used on this server and the biggest non asura use i can think of at the moment is the major boost it provides to increase SP recovery. If you can think of more, I'll be glad to hear it.