it's easier hand flying using manual thrust levers because of the pitching effect of thrust changes. Far easier to set a fixed thrust, fly the correct profile, and see what happens to the speed.
When in doubt and you have been given different opinions, then stick to the professional recommendations by the manufacturer. In the case of the 737 series, if youy are going to hand fly the aircraft other than take off and initial climb, then switch of the auto-throttle system altogether. A similar principle applies to using the flight director in the split-cue method. Either use the FD system as it was designed or turn it off completely.