The viseo of the Calidus,
To me it appears airbourne (so flapping/sailing is very unlikely in my opinion), it appears to have a high nose attitude. It appears to torque roll to the right. I'm not sure why flapping comes into it and it does not look like a reduced G situation unless the stick was agressivly thrust forward as the pilot realised he was behind the curve.
If the mast was broken, as we are told then all bets are off as to what the stick is doing, what pitch angle he is at and what control inputs take place.
In my opinion the video does show quite a high ground speed for that pitch angle and rate of climb. At the very start of the video there is a wind sock showing very light (and so I suspect) variable wind direction. The sock appears to be a long way from the gyro so the wind speed and direction could be different where the gyro is, it could even be a down wind take off with an attempted climb inisiated too steeply, resulting in a behind the curve issue, followed by torque roll and mast breaking on impact. Blade speed and colour can be deceptive at these distances on a hot day (light refraction and shimmering) and with such a short low quality video it's not easy to define.
Not sure where the open canopy theory comes from, maybe others can see a canopy opened, or maybe the pilot is saying that, not only was the canopy open but also the mast broke. It is not uncommon for pilots to run through check lists, then have to reopen a canopy to reduce the green house effect due to over heating. thus one of the last things they do before take off is canopy closed and locked, line up and take off which is sometimes out of check list sequence.
.... now I wait to be shot down in flames !