So? You get the Tenebrium skill for all your party members so you no longer get infected with Rot from them and then they can use Tenebrium weapons....all the melee skills still apply, what's the big deal?
Here says otherwise
http://www.gamefaqs.com/boards/672174-divinity-original-sin/69598789And i'm running with a party of two 2h guys + rogue + mage, i cannot respec my companions, so IMHO bad design flaw to introduce a late game skill making the invested point pretty much useless or barring some of my chars to use some type of weapon/upgrade