Renegade,
Yes, he would have been below the declination line on a windy day. Based on his apparent rate of closure, pretty fast, I don't think there was any wind. He slowed, probably below Vso, in low ground effect over the grass prior to the concrete. I expect this is necessary without the help of headwind.
A brisk walk apparent rate of closure is easier to judge, with the steeper approach, but there is less time in low ground effect to slow below Vso. There was about the same distance over the grass, before the concrete, which he utilized for the hover taxi approach. On a windy day, he could make an apparent rate of closure approach to that grass and have about twice the length of runway.
There is no way to hover taxi prior to the approach edge of the mesa because there is no low ground effect until arriving over the mesa.
If he had to depend on an airspeed indicator, or any other instrument, he would not be able use that field.
flyingpile,
The only people I know who call airplanes piles are crop dusters.
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