It seems that even though they made a change to 334.80, it still refers to 310.15[B][2][a], so it should allow the practice of running multiple wires through the same large diameter hole to enter and exit the top and bottom plates of a stud bay without any ampacity reduction, since the 24-inch allowance is intact.
It appears that wires running vertically inside the stud bay itself or horizontally through holes in multiple studs of insulated walls could be where 334.80 wants more attention to separation during installation.
I think since most of us already use those NM stackers or something similar for support and to maintain clearance from the stud edges, it should pretty much be business as usual when running wire vertically in insulated stud bays. I could see a possible problem though, when running wires horizontally through multiple stud bays in insulated walls. Maybe just drilling more holes to separate the wiring would sufficient.
