Hey, thanks for the input.
I was mainly interested in what the general school of thought is on this. I have seen some photos ( for example: Tedd Benson's The Timber Frame Home pg. 56) of similar frames with plenty of kneebraces in the plane perpendicular to the common rafters but none going the other way (i.e. from eave post to tie beam). I assume these frames must be relying on structural panels or sheathing to resist lateral force, but was curious about the rafters acting as a brace in some fashion. My frame has a 28' x 36' footprint (ridge goes long ways) and will have 3 10" x 10" pine posts supporting the 10" x 20" structural ridge. I think I will have to place larger rafters over gables and center post (principal rafters?) and brace these back to posts to help with shear. How does this sound? any input is helpful. thanks again, Steve.