Les,
Don't think you are hijacking at all. I think that the balance between:
-- Standard powered vent (Fantastic Fan/Maxx Fan/etc.)
-- Large skylight (Heki etc.)
Is a very real question. Gets more interesting when you compare what works for dry desert vs. tropical rain forest aka anywhere south of the Mason Dixon line in the summer.
At this point (and somebody please correct me if I'm wrong) there is no air conditioning unit which can be safely run all night (say, twelve hours) on batteries. (Exceptions might be a REALLY big truck or trailer with a relatively small bedroom, so that you are not trying to cool the whole thing.) Thus, for those of us who plan to spend a lot of time away from campsites with shore power, we turn to windows, vents, and fans.
It seems to me that a large skylight will lose the greatest amount of heat, when open, but you probably still need a powered vent, especially if it is raining. Similarly, side windows that can be kept open in the rain are a really nice feature. And while I have no plans to go back to Africa, I still love the idea of a roof vent for critter photography and roof access. The problem is that smaller vehicles, like the Tiger, run out of roof real estate very fast, especially if you want a lot of solar, as I do.
My thoughts. I welcome comments from those with more recent experience.
FBC