That ladder is well off the 1:4 ratio too. I've just tried to measure it with my ruler and I reckon the top of the ladder should be around where the window cleaner's shoulder is; but obviously it's not long enough to do that; hence the dodgy angle.
I don't think I know this window cleaner, Mike, does he do any work that you know of round the Chepstow area? He isn't the miserable sod in a beat up Mondeo who spends an-hour-per-window and also does gardening is he?