I cannot see what all the fuss is about. Directly and indirectly you are all right!
I think everyone here has acknowledged that a twin will bite if you are behind the game. I, for one, hands up, was behind the game when I was least expecting an engine to go on the climb out from Pietermaritzburg (Oribi)
in a Cessna 414. Fortunately, I had some height, but I very nearly put that
on its back.
....and when it happens, she will go as fast as mad_jock
explains.
Whether we call it "firewalling" the live throttle OR advancing the throttle to max power is neither here nor there, it's the same thing.
Personally, I wouldn't advocate use much more than 5 degrees of bank either way with an engine out. Yes, you can apply more, but strictly speaking you are in unknown territory, and will not find anything to substantiate this in the POH.
I have many hours on the aircraft type in this dreadful tragedy. She has a reasonably good single engine climb performance, but she is a slippery ship.
Safe flying all.