I wouldn't do it! I think that Jeff has a lot of courage
Whilst I am fairly confident about actually being able to set one of my poles up that high, as it is fairly straightforward against a building, I'm not confident that I would be able to satisfy a Health and Safety Inspector that this was a well assessed and controlled risk; obviously Jeff has looked into this and has decided that he can.
All it will need is one high profile accident at this sort of height for the HSE to step in and start regulating exactly how poles should be used and this would have a knock on effect across the whole of our industry.
I would attempt this job under certain circumstances though, such as:
Permanently blocked off roads, with no vehicles parked within 100ft.
No other workers on site (cherry picker next to pole, etc)
All operatives wearing Hard Hats (the first thing that the HSE would pick on)
A second pole that was attached at about 30ft down from the top and going sideways at an angle of about 20-30 degrees as a support pole, or twin roped lanyards (probably easier).
A third operative to control hoses, water flow etc
A fourth operative to take off/put on sections
A fifth operative to do the same for the support pole.
If all of the above were in place then I would be happy writing out out a valid risk assessment and method statement. To make such a job pay you'd need about £500 per hour to cover all of the operator costs!