Thank you so much!!! Gah, I hated the old design!!

They do on some. I assumed that they would be immune but I tried it last night on the Foreman Crusher. The tank wasn't necessarily having difficulty during Frenzy but he called out to help if any of us had anything. I activated Obfuscate, and saw the nice little debuff on him. After frenzy, the tank commented that he didn't receive one hit. I informed him of Obfuscate and now we save it for each frenzy. Tried it on the droid puzzle boss next and it worked as well. So, as far as confirmed list, I have this: Foreman Crusher Droid Puzzle Boss