I love that some people assume everybody just PUGs these things and can simply grab an Inquisitor. I have three friends that I run with all the time (Powertech, Marauder, Assassin, and myself - Operative) and we're not interested in splitting up. We got him down last night, but it was a headache. Just because Sages and Sorcerers are flavor of the month doesn't mean BioWare should be designing encounters around them.
Then you have a comp that can kill the fight.
Either use Grappling Hook when he starts the lightning channel, and then have your Assassin use Overcharge (or w/e it's called) or just have the assassin use Spike and then Overcharge. Either works.