YOU HAVE TO BE JOKING! Are you blind?
For anyone to 'excuse' this sort of behaviour is very sad.
This sort of thing, amongst other more 'serious' incidents, is the very reason that I refused to renew my PWC instructors certificate. I tried to keep an open mind, but have come to realise that the owners of these craft are largely beyond help. It would be a shame for most of the responsible owners, but I think they should be 'removed' from all but the most isolated un populated parts of the planet.
IRPCAS aside, this is clip shows quite simply, outrageous and dangerous idiocy. If that were my boat alongside the pontoon, I would not be able to help myself!