Yes, I was just discussing the use of people as scale cues with a pair of architects, and the way placement of people causes the viewer to imagine what they must feel like, in the scene, i.e. to personalize it.
Careful placement of people can do wonderful things. Of course, there are no firm rules.... effective landscape images may or may not have people in them.
I still stand by what I said earlier in the thread- I think it's a bit ridiculous the lengths to which some photographers will go, to try to obscure the evidence of humanity in the modern landscape. There are few out there courageous enough to incorporate all the power lines, the roads, the urban monotony... and all the other things we consider opposite the classical landscape.