When a blank is cut, only so much stress relief can occur. The pretty little swirlies are all tied up in knots decades before I ever see them, and I doubt they plan on changing their relationships when I cut through them.
Regrettably, there is no definitive way to prove a negative.
Apparently CZ, you have never cut a walnut tree to produce blanks. The English Walnut tree that I had cut up about 15 months ago is air drying nicely. But despite my care in handling the wet slabs, I expect to have some checks and stress cracks as they slowly season. They have had the ends heavily coated with a few coats of polyurethane and are stacked and stickered out of the weather. But one slab already has a nice crack running along those pretty swirlies that I had hoped would grace a buttstock. This is not a huge unexpected tragedy. This is the nature of figured walnut. I can only hope that I don't lose more. I had the same experiences with a truckload of black walnut slabs I purchased some years ago. But the price was so nice that the inevitable losses due to checks and cracks were quite acceptable. As to your statement about kiln drying... if kiln drying was just as good as air drying, everyone would do it. But of course, even kiln drying can be rushed too much with bad consequences.
