Isn't the Thrash from Madness better than Voltaic Slash?
I honestly don't know, but I would think VS is stronger. Madness thrash gets a surge buff from claws of decay and base damage buff from unearthed knowledge (if you keep it up), other than that the buffs are shared (exploitive strikes, thrashing blades). I'd think a critical hit on thrash would beat out a crit VS, but VS is more consistent, and actually leads to useful procs to buff shock and discharge. Thrash in madness is just filler. Strong filler, but filler nonetheless.
And that TOR assistant looks incredibly useful, especially for when you have to track deathmarks between multiple madness inquisitors.