Peter, - Serious question ...
Do you still get a buzz out of the walk, when you've done it so many times and are having to drag along a complete bunch of strangers (Some of whom will, no doubt, be a pain in the ass)?
I was offered a similar opportunity while out in Cappadocia (taking groups round the major walking route about twice a year - perhaps leading to doing it all season.) One of my main concerns about doing this type of thing is that I'd end up spoiling the "feel" of the place for myself, and no longer enjoy it ...
... Over to you ..?