Nick: I'd like to see those charts, especially for the R22 as thats what I'm instructing in. If your descrption is correct, (and I'm not doubting you) I guess I've never been in actual VRS. I have never allowed a demonstration of VRS/SWP to develop past a 500 fpm decent rate which would mean that I wasn't in VRS by your definitions.
I find that when I induce SWP with a tailwind and I attempt to make it worse by pulling in power the helicopter (R22) has a reduction of the climb rate and an eventual climb. Certainly not true VRS if an increase in power is supposed to result in an increase in rate of decent.
So what am I really in? SWP but not VRS? I certainly am settling, have not reached a 800fpm decent rate, have power, and am yawing and shuddering until I recover.
I still teach that downwind quickstops are dangerous, maybe I'll just be changing the explanation of why from the danger of VRS and other factors to just the other factors. Simply put I wouldn't want any of my students making a downwind quickstop, regardless of VRS or not due to the other dangers already mentioned.