I think that sequence in that video is on a Via Ferrata at Thones (not La Clusaz). I did it last summer.
Seemed like the hardest single sequence on any VF I've done in France. I'd say the overhang is so sustained and severe that if it were on a free rock climbing route its difficulty would be rated Euro sport 6a (at least).
I've seen a report that someone once died on that sequence. Nowadays they provide an alternative less steep to the right side of it, in the form of a metal ladder -- so it's just optional to choose to climb the very strenuous sequence shown in the video.
I have a third (much shorter) leash-with-karabiner on my harness which I use to rest on sequences like that by clipping to one of the metal rungs and then hanging off it. The advantage of having a shorter leash/lanyard is that I know the rung will still be easily within reach when I'm finished resting.
Yes I agree that aking a fall while relying on a Via Ferrata kit is a bad idea - (though falling on an overhanging section might be less bad than some other situations).
Taking a _second_ fall on the same kit without having replaced (or at least somehow adjusted?) key shock-absorption component(s) is a really really bad idea.
Ken
Post edited at 06:24