Jeremy Riggs new SIC

Race season is just around the corner.

17'4 Bullet with a little extra foam trimmed off the sides.

I'm trying to separate the marketing hype from fact when it comes to the tail sections of unlimited downwind boards. Clearly there's a stability trade off but is the narrow tail to help with tracking or to reduce volume to allow the tail to 'sink' into a wave or swell?

Can a similar result be achieved with a wider, thinner tail that similarly 'sinks' into a wave but provides greater stability?

Your thoughts please?