Reading other contributors, it seems one big issue is "mixed operation" - manual flight with automatic thrust. Like Denti, I fly the baby Boing (738). It is either all manual flight or all automatic. We fly short haul with regular short legs so are in fairly recent hand-flying practice. I am still in the RHS and the 73 is the only airliner I have flown so bear that in mind when listening to my opinions.
When disconnecting one, you generally disconnect the other, though I have flown occasionally with the AT inop but used the autopilot (RVSM requirement). Unlike Denti's company, we do not use the ARM mode in manual flight (that is a debate involving plenty of religious schisms in itself!) so for a go-around in manual flight one just stretches out the thrust arm, sets a fixed thrust level and sticks both hands on the control column. When manually flying the 73 one is very aware not only of the speed but the thrust set - even if the speed is good, a glance at the N1 will tell you if you need to add or reduce thrust in short order before you get any observable trend.
The difference is in the Airbus/777 where it appears the SOP is AT use through touchdown, which I can see could lead to a lack of awareness of actual thrust, and losing it I'm your scan while simply controlling the flight path.