I've flown planes without autothrottles
and with modern boeing autothrottles.
it was just so, so hard to move two big levers (or four for that matter) forward and back to control the engines.
go= forward
go for all you are worth, forward till you bend throttles over mechanical stops.
or
go...engage autothrottles to pre programmed thrust setting, watch and feel thrust levers move by themselves
but be sure clutching mechanism works properly and moves them together and make sure the thrust setting is correct
soon, there will be automatically tying shoe laces!