I am going to forward your response to my speaker builder. As I look at the craftsmanship of my horns up close, it has to be an absolutely fulfilling job once completed. Who know, maybe you will turn my next horns!!!!!!Will - I spent the last 3 years being trained in this lost art form - my teacher is 90, which says a lot about the “lost” but boy does he know the art. I make a lot of conventional bowls, pens, platters, vases, hollow forms as well as horns. I was trained using original tools / chisels rather than the poor carbide scraping substitutes that produce a poor finish. I do segmented turning as well as from solid blanks like your lovely horns. My latest project also uses solid blanks.
Maintaining the integrity of a turning is very much part of the skills in construction especially for segmentation. However if one uses very stable kiln dried blanks rather than green wood, stability is extremely high especially if it is jointed to another substrate in a manner that prevents movement.
But to get to the heart of the question. There are ancient wood turnings that still have their full structural integrity so I wouldn’t be concerned about your lovely asset.
Finally there are modern means such as torrefying wood to improve stability as employed by OMA. Also the types of finishing used.