Very accurate description of edible gold. It's purely there to make it look fancy and to justify a high price, but adds nothing to the actual eating of the dish. I'd be interested in trying salmon nigiri with truffle, but not in a lump on the top like that is. (and not how I'd want the wasabi either!)

Form the rice, dab the wasabi on it in 3 places, grate the truffle over the rice, place the salmon over the top. Enjoy.

Sure, it's go no show, but it'll have all the flavour in every bite