Not true:
- hearing high rotor rpm
- feel high rotor rpm vibration
- proper recovery
Same 3 for low rotor RPM
These things you can perfectly train in any modern Twin with a training mode H135/H145 for example, but I am sure other types like B429 have something similar. But you train them with a much higher safety level, as you cannot go below below a certain critical rotor RPM for example without the training mode automatically recovering RPM.
- overpitching in flight and recovery
Is a non event in a modern military helicopter… most can go to -0,5G and still be controllable…. not teetering types in the mlitary inventories of the modern western militaries.
- proper collective / throttle correlation in all phases of flight
Is a non event in modern military helicopters… they are generally controlled by (dual channel) FADECs (no throttles at all) or digital engine control units. In case of the latter one can still train with the throttles, for example in a H135, Bell 429 or A109.
- differences of said correlation during a running landing
As stated above, sort of a non event OR trainable in the single channel types that still have twistgrips or throttles.
- effects of higher G-load on rotor rpm
Can be trained perfectly on all Twins is exaclty the same.
-right stuck pedal landing without ground run using throttle
The types that have throttles, such as H135, A109, B429 etc, this can be trained as well.
We can do all that for $500 an hour, no need to teach hovering at 3k of tax money per hour.
That is really the only valid argument, however for that extra money you have the added safety of a Twin, more representative training as all operational types are Twins, ability to Twin emergency training such as OEI landings and the ability to perfom IFR training, advanced mission training as well.
I boldly state that you have much more control over an old Schweitzer than you have over that fancy EC155 of yours
Might be true, but this control you have in a Schweitzer is not required in a EC155 or any advanced or as you call "fancy" military type. As such control is only relevant if these pilots will fly these basic Aircraft in the future, which they won't. (at least not within their militaries)