I'll start by saying I think from Gulfplt's description that it was a partial loss of T/R control. Not so?
My experience has all been simulated thus far, in the simulators at Bell/FlightSafety (FS) in Fort Worth and with the Canadain Military (CF) in Gagetown, N.B.
It was mentioned before that FS's assessment of vertical stab effectiveness was optimistic. The CF agreed and adjusted their aerodynamic programming accordingly. In the sim the response was pretty basic, lower collective, roll off throttles if you have time to think about it, and cushion at the bottom. Like most of these items, practice allows you to land something that was extremely difficult the first couple times.
I have also simulated countless stuck pedals of varying degrees in the hover, climb, cruise, descent, even on the ground prior to T/O. This is in the RH22, RH44, and BH06. I have seen several pilots try to pull pitch and climb away when the right yaw got away from them and they wanted to go around and try it again. I make a point of maintaining the failure, just so they can see why this is such a lousy idea.
Invariably the right yaw accelerates beyond their ability to focus on the horizon and they lose the ability to maintain a level aircraft, any wind/airspeed and associated weathervaining only exacerbate the situation as the tail whips through 90-180ish yaw. I rarely let it go more than one full rotation and never yet has the pilot thought that I took it too early. The reaction I teach in this situation is to stop the a/c (cyclic flare to zero groundspeed) and perform the failure as per the hover. They are already close to ground now so it's a short hover chop to the ground.
I would love the opportunity to get in a light helicopter sim and compare rotation rates with what we get for varying aounts of stuck right pedal in the hover. What I generally use is a stuck right pitch sufficient to maintain a right rotation in the hover despite immediate closing of the throttle.
Now, to respond to soem comments above:
Spins: A fixed wing spin and a rapid yaw are two completely unrelated beasts. The autorotation is the closest rotary equivalent to a plank spin, and is handled quite well. Control in the spin gets quickly out of hand because you are sitting out in front of the center of rotation, trying to look at a world that is moving too quickly to focus on. The immediate (normal) reaction is to focus in tighter to the a/c to pick up details, taking the horizon out of the picture, and pitch control gets ugly. Additionally, if the a/c is rotating at, lets say, 60 RPM, easily achievable, then the RRPM is effectively 530 - 60 = 470 RPM (this is for the R22) or 89%. For the R44 it is 85% and the 206 it is even less. Even more pitch is now needed to effect that climb, meaning more power, a higher rotation rate, and a lower effective RPM. Overtorque or overpitch follow and game over.
Running Landings: Nice if you have a place to do it I guess. Here we rarely fly in anything close to hospitable terrain and always teach a spot landing using cyclic flare and landing as per failure in the hover. When I was on mediums in the IFR world the running landing was standard but there is a lot more machine to toss around.
Of course, these are my opinions, they won't cover every situation, and feel free to disagree and tell me so.