I can't see why not. The neck is more than long enough, the string pull forces are quite high, and the whole instrument is more sensitive to changes in weather than are the instruments that always have truss rods. The difference between good action and unplayability is slight, so why not have a truss rod? There's plenty of room under the fingerboard for an allen-key adjustment nut. If you had one, you could tweak neck relief as needed, with every change of string brand, or even if you were going from mostly pizz to mostly arco can't understand why not--any ideas?