A [-4] catch would be mathematically accurate, since it's half Physical Immunity. Though I would like to know what the forum thinks it should cost. And I see no reason why a half all damage power would be bad - if anything, it's a great power to tack on to end bosses, since even with consequences they tend to be too fragile if you want them to fight solo.
All of this, of course, is my opinion. I am fairly new to the game myself.
Also, for the 10+ Fists rolls, I'm guessing high skill cap + large amount of stunts + large amount of True Aim and Demonic Copilot-style powers. Or maybe something like Sponsored Fists, with debt paid off by excessive self-compelling.
...Assuming he does it himself. If combat boils down to "give that guy all the tags you can", then 10+ should be par for the course.