Woody42, the version in that clip seems to be a slightly later model than the infernal device I knew. For one thing, it has a proper moulded plug cap, rather than the screw top plug I knew....
The problem with the screw top plug was that tall greenery would fall on it after being chopped down, efficiently shorting the exposed plug top to earth thereby stopping the engine. Which was almost impossible to restart if hot.
Back in the early '70s, my late father borrowed an Allen Scythe to tackle the triffids in our orchard.
We should have known better.
After it had been unloaded, the first time he started it, it lunged forward in the traditional manner, to take a bite out of the can of petrol/oil mix which had been delivered with it, causing the entire contents to escape.
The following day was a Sunday. Being an idle student down from university for the vacation, I was in bed listening to my father's colourful vocabulary whilst he was triffid-killing in the orchard. We lived in the Old Rectory right next to the local god-shop and I could clearly (and somewhat guiltily) hear the good folk of the congregation happily singing away. At the end of one hymn, they'd just got to the 'amen' at the precise moment the Allen Scythe decided it would stop its engine after a dead triffid fell on the plug..... Unfortunately the moment of holy silence in the god-shop between the hymn and the vicar resuming the service was punctuated by a yell of "YOU BASTARD THING!" from the orchard. I lay giggling like an idiot, in the sure knowledge that if I could hear both my father and the congregation, then they could probably hear him as well...