He used so-called SPD pedals and shoes, which I understand to be
clipless. They helped for climbing because he could also pull on the
pedals. For the first half hour he managed to unclip his shoes in the
case of a fall, thereafter he was too tired and just crashed into the
tarmac. From this description and the fact that the total riding time
was 9 hours, I guess it happened quite often. This is a new approach
to falling for me. Possibly it makes more sense because the speed is
low and the tarmac is near in case of a forward fall (because you
climb).

It certainly looks like I am promoting a new trend in 'how to get off
a unicycle the hard way'... well, I'm not! ;-)
I only 'crashed' once during the 3-fold climb, in the last bend, about
50 meters from the summet (last climb). It was close to 10 pm,
completely dark and the car that followed me had to take the turn at
the inside (another car was coming down) = no light for me = crash.
The most difficult part in riding with clipless pedals is to get the
confidence, knowing that one single moment of distraction is likely to
end in a dive...
Obviously, the use of clipless pedals only makes sense (at leat it
does to me) when riding on normal roads. Using them for off-road /
MUNI is probably not a good idea.

So far for now. I will put a page in english on the web in the near
future, describing the 3-fold Mt Ventoux climb from a unicyclers point
of view (unlike the dutch page that is aimed to a 'normal' audience).

Regards,
Lode De Paepe