Graviman,
I emailed you the simple drawing I made. Anyone else who may be interested feel free to ask as I would be happy to share it.
I would love to make a CAD model in 3D as I agree that would be the easiest way to see how things work but I work with CAD programs about as well as I sing and I can't carry a note in a bucket!
Now on to something I know at least a little about. To answer your question about turbine torque lag. There are actually two types of turbines used in helicopters today. The free shaft turbine and the direct shaft turbine. Most current types use the free shaft variety. This type can be described as a jet engine blowing on a pinwheel. We have basically a jet engine with a second turbine mounted close behind. This second turbine is not attached in anyway rotatonally to the jet engine rotating assembly but only to the out put shaft of the engine. When the pilot increases load on the rotor system by pulling up on the collective we automatically increase fuel flow to the engine which creates more hot gasses to impact the second (or free) turbine. A by product of this is that the jet engine (known as N1 or NG) which has no load on it other than that of the compressor drag increases in speed. Normally this happens very quickly and becomes almost transparent to the pilot. However we do have two limits to consider.
First is the fact that as we increase the load and subsequently fuel flow we create a great amount of hot gas to impact our free turbine which changes this energy to a twisting force we know as torque. If we arent careful the torque may be greater than the loads the rest of the drivetrain can handle resulting in broken parts. So one cause for this "lag" is the simple fact that we need to avoid overtorquing the drivetrain. In real life the engine is quite happy to produce more torque than the drivetrain will handle and in a very short time. So, you could pull up hard on the collective and the engine would quickly adapt to the load and you would see the torque gauge run right past the redline without much lag at all.
The other limiting factor is compressor surge. During this power increase phase we need to meter our fuel carefully so as not to build the fire in the engine to fast. If we do the rate of compression becomes less than the rate of combustion and the fire starts to squirt out the front of the engine and not the rear. This is what is known as compressor surge. So we can say that if we had a ful flow of 10 gallons per hour and we wanted to increase to 50 gallons per hour we couldn't dump all that extra fuel in at one point or we could have a surge. We can increase the fuel flow over what we have and as the engine accellerates and we have more air being compressed we cna continually add more fuel. This situation does cause a slight lag in power output in a turbine engine however with the efficient new compressor designs this can be minimized to a point where it is almost a non issue.
My thoughts on the rotor governor are that it would help with the complexity of the fuel control system of the engine as now it would not need to have a governor system built in. It would help with entry into autorotation as the reaction time needed would be relaxed greatly. There may be a slight decrease in pilot workload when considering "getting behind the power curve" but this is usually an issue with piston engine helicopters more than turbines. So for your R22 example with the old Lycoming mill I would say it would be great as you have no torque limit to concern yourself with. The pilot could pull all the collective he/she wanted without fear of getting ahead of the engine. In a turbine ship the bennefits are much less since you would always need to fly the torque gauge as the engine could overpower the drivetrain.
Once again my diarreah of the mouth has spread to my typing fingers. I hope my explanations helped at least someone and I didn't teach everyone stuff they already knew. Now on to find Mr Jackson!
Max