FYI-Some of the more progressive thinking builders in this area are starting to use radiant barrier as a underlayment for one coat stucco systems. It has the advantage of allowing the stucco subs to use the regular foam at the attic spaces instead of AIS board or R-Guard.

I'm sure the reduced heat is minimal tho, because they have yet to require the foil on the roof sheathing....oh, well, they are after all dinosaurs. I guess we should be thankful for the small steps...