what the heck indeed -plans aren't perfect. think about it: if you mate the end of the fretboard extension with the side of the utg you now have all the width of the upper bout
and both sides of the rim of the guitar to dump that stress into vs. only having the much smaller contact of the fretboard extension alone in that one small area of the top. world class builders (like somogyi) take this into account, factory guitars not so much. it's a
controversial move for sure, as many will say that "so and so doesn't and their guitars last forever" but physics doesn't lie here.
you're doing fine so far though keep it up!
