(( Well, still, humans who are infected by a virus that makes them drink the blood of ANY creature to survive is kind of crazy. And some people may have conditions were they are extremely sensitive to sunlight, but they don't friggen turn into ash when they get hit by it. :P
And the point was to give human Hunters a real decent fighting chance. They should be feared, and feared for a reason. And the power of the mind is a very real possibility, at least in the parameters this story sets.
Though I recommend not stating it as mental prowess for sure, just to leave some mystery. Vamps shouldn’t really understand it either. The way it works though, has nothing to do with the power being Holy and the Vampire being evil, it damages anything it hits. ))