In view of SeanK's post I will clarify mine.
It was probably misleading as my round is mainly terraced houses built in the early sixties, almost all of which are arranged in blocks. The windows are averaged size and are for the most part very straight forward. We're talking two up, two down, front and back and not much more than a few steps between them on each property. Not many of the front gardens have walls or fences and most of the back windows can be accessed with a 15 mtr hose leaving the trolley outside the garden. I have a handful of quite large back gardens where it's easier to take the trolley in and use a very short hose to prevent it getting caught on whatever's laying around. However, the times I stated were accurate for most of the properties I was cleaning yesterday.
I recently spoke with another window cleaner that I met though, who had gone back to trad with ladders as he found wfp much slower for his work. He didn't say how long he'd tried it for however, and when I met him he was cleaning houses like mine, so I don't know why he found it a problem. It may be he didn't stick at it long enough or have encouragement from fellow windies to persevere.
Me personally, when I first looked into WFP all I could see were all the negatives and very few positives other than the most important one of not working at height. After a few weeks of WFP though, most what I had seen as potential problems melted away. I found ways to work round them. Now I would never go back to cleaning from ladders even if I could, and after eight years at wfp, I still occasionally find quicker ways of doing things.