The point I am making is this: Whilst the airframe accelerated upward, the Nose Pitched Down. It is at this exact moment that the a/p quit.
The Nose is "trending" UP, the VS is trending DOWN, and that signifies...
"MANEUVERING"
For five seconds, the airframe is not stable v/v level, speed, or acceleration. Well and good to pontificate re: what PF must do, but this massive airliner is spunky as a little Robin, and that ain't right.
"I have the controls...." Whether OR NOT the PF knows the genesis of disconnect, he is well within his rights to assume the a/p has left because of control demands, not ICE. At this point, he does not know, and after two plus years on, neither do we.
I sense HN has some misgivings about a/p in the stink. So did Smilin Ed, and so do I. The A/P has quit, the a/c is wanting management, and the Bus has reverted to "Other than NORMAL LAW". Free to STALL, you're on your own. The BUS has left the building.
Make NO mistake, what the pilot does now is the precursor, and (I think) the procuring cause of manually induced UPSET and LOC. Is there a 'sit on your hands' command for the AUTOPILOT? Thought not.
Wanting to establish a 'normal' flight path is a natural for any pilot flying an airliner. Perhaps there is a flaw in the training concerning this situation.
NOT "I have the Controls", but instead "monitor the Stick, No Touchee".
Wait, what good is there in 'monitoring' something that does not move?