One of the Tyne's idiosyncrasies: during climbout from LHR in the early 1960s one would hear CL44s (can't remember which operator) momentarily throttling back from climb power for a few seconds (approx 5 miles from the airport) and then throttling up again.
A few years later during Vanguard ground school I have vague memories of an instructor telling us that BEA originally had an SOP doing the same thing at top of climb, to 'offload the splines' (whatever that meant). Apparently it was common practice for the flight crew to do a PA at the same time to distract the pax from the sudden silence from the engines. (Although one would wonder why the throttle back wasn't done in engine pairs - inners together then outers together to reduce thrust loss. We'll never know . . .)
Another Vanguard idiosyncrasy: on the approach the props were operating in the constant speed regime so we judged engine power by fuel flow rather than torque meter readings (not precise enough). Every change of power setting also required a rudder trim input to keep the slip needle centred.