I've often wondered about this. Seems that it's got to do something. Spanish makers have traditionally thinned the sides out to 'weaken' them where they join the rims. And while like the Japanese master metallurgists who made superior swords by folding metal, they didn't really have the physics to back up as to why it made it better but intuitively they were very wise. I think Trevor Gore had some pages dedicated to thinning the edges.
I've always thinned out the edges of the lower bout.
I've done this purfling scheme a few times and indeed have one guitar made in the 1920's where the inlay no doubt even goes past the kerfed lining. But here there is barely .09in or so fully attached to the lining and the rest of the way the top is thinned quite a bit to the binding.
I wonder if this does indeed loosen the top and have some sort of affect on tone.
Thoughts?
