Had I known it was an advert before I watched it and that something horrible was about to happen I think I would have been less bothered but frankly I found it nasty! I'm not too bothered about such stuff usually and enjoy a laugh, and looking back the hand looks very fake (maybe the home video style and closeness to home made it worse).
Perhaps it is a good reminder though. Just a shame it's actually designed (can't see it working myself) to sell trousers or whatever... I think whoever made it should put their energies into something less grim. The accuracy compared to genuine videos of similar events (Robinson safety Course) is worrying...
I didn't like it!
PS thinking about it further is it a genuine advert or just a bogus one for the sake of the skit?