Thanks again. Just did several variations of search in that beast. Interesting document - makes me want to be a test pilot (not really).
Again, as the overwhelming majority of the stuff I've come up with on my own, it appears this is design certification stuff. And while I guess it's conceivable you could design something with a maximum bank angle of some number of degrees, most of the maximum limits I can find are indeed load limits (2.5g - 67* in level flight). This does seem a more sensible approach to aircraft design.
I know it's not in the basic aircraft design (although certification is a different animal) because I flew the military version and wasn't limited to 30* by any rule or TO. However, I've already learned quickly that how the FAA certifies the plane has nothing to do with how the military operates an identical model!!