No one doubts the builders ability to apply core,(or apply glass to core) the problem comes down the road when an uninformed boat yard worker slaps a couple thru hulls in with out proper decoring and filling. Many will decore the hole, not many will go deep enough to decore the mounting bolts, screws etc. How many spray rails are screwed in, even bolted. Every time you hit a dock, get put in the slings etc, things wiggle, and water finds its way. I am with VPC on this one, for me, there will never be a balsa hull. Limited if any upside, huge potential downside. You can ask any one of the New Engleand boat builders for their opinion,
some of the best are here every day.
My 1985 Sisu 26 is balsa cored down to within 18" of the keel. I've owned it 3 years and as a part of the maintenance plan I removed/replaced the thru hulls, engine intake, depth sounder transducer, transom step bolts and also cut into the hull to install a bow thruster. I've never found any core damage. The boat was very well built with a lot of care.
There's no need for that just wheel time