I think of it as “power is the multiplication of MAP and RPM”. Not throttle and RPM. Try it established in cruise: change the RPM lever. See the MAP changes accordingly in the other direction.
My routine is pretty simple:
UdoR wrote:
Most pilots I know stick to these three settings all their life, by the way.
It’s all you need, and then one for aerobatics 
More RPM gives you more power reserves and throttle controls the power or thrust if you will. Landing and take off you want lots of power reserves available, while cruising you normally want endurance primarily. For aerobatics you want all the power the engine/prop can produce without braking apart (at least the aircraft I fly )
lionel wrote:
I think of it as “power is the multiplication of MAP and RPM”.
That’s true, but
Try it established in cruise: change the RPM lever. See the MAP changes accordingly in the other direction.
the MAP does not go down in proportion to the RPM going up. I.e. power will increase when you increase RPM.
Also
Not throttle and RPM.
Clearly not, as MP is not related to any specific throttle position.
I suggest a read of this initially.
The operation of a CS propeller is a lot simpler than would appear. In low level flight, say below 5000ft, you always climb at max rpm and then set some cruise rpm at which the engine is happy; typically 2300 or 2400 (if max is say 2600). You also get better mpg. And this.
At higher levels, non-turbo case, you are likely to need max rpm for cruise; you will by defition need max rpm (=max power) to reach the operating ceiling.
“Cruise climb” may not need max rpm but it depends. If you want to go from say 2000ft to 3000ft and you have lots of time, just enrich the mixture to best power (say 1300F ROP on the EGT) and climb at some airspeed which keeps the engine cool enough.
The functioning of a CS speed prop becomes quite obvious when flying a three position propeller in a TMG with an underpowered engine. For takeoff you set full fine for cruise a bit more pitch and gliding feather…look at it like a bicycle how would you (providing muscle power like a throttle) climb the Mt Ventoux with your bike…its that simple…. If you leave the pitch in climb position on a TMG when levelling off you wont make any speed …but you’ll have enough RPMs available. The advantage of CS prop it provides the same RPM irrespective if your in a climb or descent. I wish I could modify my TMG to an electric CS speed prop from MT like I had on the Taifun. Now I need to fiddle around more with the throttle to keep the rotax happy at around 4800RPM during level changes or even flying through thermals maintaining altitude.
Or just do what we do in the RAF Tutor (Grob 115E) and leave it at Max RPM throughout and set power with throttle
Yes you can do that and it will cover all bases
You just burn maybe 10% more juice, but that’s true only if you have a reasonably long cruise section. In flight training, maybe not so much.
To a large extent it is what Cirrus did, by removing the rpm lever.
Vref wrote:
I wish I could modify my TMG to an electric CS speed prop from MT like I had on the Taifun
You can have mine if you give me a hydraulic CS prop in exchange. And the crankshaft to go with it 
I operate as follows with my Bonanza.
Takeoff – full throttle, mixture set, RPM full 2700. Climb to cruise, maybe lower the prop to 2500 RPM, adjust mixture in the climb, throttle full. Level off, accelerate, set mixture to 12.5 GPH. I don’t make any more changes, often until after I land other than lowering throttle for descent and landing. Instrument approaches, lower MP to 15 inches, 105 Kts, intercept GS/GP/+V just lower the landing gear. So as far as the prop is concerned, it has been at 2500 for most of the flight, except for takeoff and climb to cruise.
@NCYankee at typical cruising altitudes, say 8,000 feet, it probably is worth varying the RPM occasionally to keep the governor oil warm and refreshed. I tend to operate between 2400 and 2500 RPM and like yourself only go full fine for take off.
