There is a real mystery here for me. I understand this was a check flight for the RHS pilot; part of a conversion course to the NG. In light of that I would have expected all the crew to be very alert, certainly the T.C. Let's wait until the CVR is released, which hopefully will answer this query.
About guarding controls. I am dismayed at how many students/cadets on TQ course LST's fly the NPA & Cirle to Land procedures head in and hands off. This is a basic lack of discipline in the teaching phase. Bad airmanship. 150hr cadets do not necessarily yet have airline airmanship and it needs to be drumed in from day 1. I see then same thing with PNF not covering the rudders on takeoff or final approach. I'd always thought it prudent that, in critical stages of flight, PNF should be able to takeover control instantly.
The same should apply for PF should the automatics mis-behave,