Working with some buffalo horn and made me think of this thread. I agree with what Chuck said but it doesn't even stabilize well either. I always warn customers wanting buffalo horn. It can shrink, crack, twist, warp, etc, etc.
I always tell customers to rub mineral oil on it from time to time to keep it from drying out and cracking. Treat it the same way you would ivory.
Work it the same way you work ivory, sharp belts and keep it cool, sand to at least 600, buff with muslin wheel with green or pink compound. If done right buffalo horn will shine like a black mirror.