This is low-nitrated material, and the only issue there is thermal runaway that you don't have when applied as a guitar lacquer. That nitrocellulose form is on

This is low-nitrated material, and the only issue there is thermal runaway that you don't have when applied as a guitar lacquer. That nitrocellulose form is only really a problem in bulk form, like back when it was used for movie projection film. Flakes of the lacquer just burn fast and may continue burning without additional oxygen, but the thin film inhibits any detonation waves across the surface, while the liquid lacquer form inhibits such by dilution in a solvent.