Army too - we cross train a lot more than is thought. Allies, at least, and I can’t speak for the Navy, they do things differently, since they have different priorities. After all, getting each others routines down is vital.
But Chief? That’s a no in my book. Too risky.
If it is just a “grunt, ceremonial type position”, why have it? Have an official liaison position so everyone is clear. I can make coffee, type, answer the phone.....