Manual flight with autothrottle/ thrust is not a good idea, and I do not practice it, neither does my company. either all ON or all OFF. combining makes things jot only more complex, it confuses both the aircraft and the crew.
It seems more and more likely that this is one of the contributing factors.
Over and over, I see Captains and FO's blindly relying on the autothrottles, never putting their hands on the thrust levers to feel their reaction ( Boeing here) or at least monitoring the thrust trend and value ( on AB).
We do it all the time at my airline with no issues.
So what do you do prior to landing? Turn it all off? We click off the AP at 500ft on a visual and pull back power on RETARD. That goes against your line on thinking.