I can take my little ol' FH1100, go up to altitude, bring 'er to a downwind hover, get a decent descent goin', the pull up on the pole and watch it come down faster while not even getting near a power limit. Done it, in fact. Done it in a 206, too. Maybe VRS is a myth, or maybe it's "extremely rare" but I can experience "settling with power" any time I want to.
In fact, I used to demonstrate this to young aspiring commercial pilots. Photographer in the back, wants to shoot something on the ground from a certain angle - which puts you in the position of being in a downwind OGE hover and (of course) sideways to the object. You sit there, looking out the side window (not really at the instruments), maneuvering around at "the photographer's" command, "up a little...now back...down a bit...hold it there...down a little more..." Suddenly - whoa! - you find yourself in a big descent and pulling pitch doesn't stop it. It's a fine, easy, fun demonstration up at 3,000 feet, where the ground is nice and far away. But, I ask them, what would happen if you were only at 500 feet? It's an eye-opener, baby.
And yes, I have done such ball-buster photo flights. He says, "No, we can't be moving - I just HAAAAAAAVE to get this shot from this specific angle." And you go, "Yeah, but the wind is...I mean the ship doesn't...<sigh> oh okay, we'll give it a try." Hey, we were all young and stupid once. (Okay, some of us were.) Now I know better. Back then I didn't. Nobody took me up and showed me some of the wacky situations I'd find myself in as a commercial pilot, oh no!
So I dunno...maybe VRS, maybe not. Or maybe there's something else going on in the rotor system - weird flow transients or patterns that are hard to quantify and equally hard to understand. And come to think about it, a momentary RoD of 800 fpm in a hovering or descending Robbie might not be all that hard to produce. I mean, think about it. Think about being up at 400 feet and needed a whole 30 seconds to get straight down to the ground. Not a very fast descent, wouldn't you say? Doesn't seem all that amusement park-ish to me. Maybe VRS sometimes only needs a half-second of that to get excited.
Rotors are weird.