Now first of all, let me say that I'm not claiming I've found a new technique, this has probably been posted before. But it's the only thing that has helped me with the throat hit so I decided to share this from my experience.
I've always had trouble taking more finely milled snuff (I'm not talking about the infamous Indian white snuffs or anything like that, just some Toques and Wilsons of Sharrow). I hated how I couldn't take some of my favorites without getting a throat hit and coughing. I tried dozens of techniques - doing it with moist fingertips and nostrils, using a snuff spoon, placing my pinch to the side of my nose, taking large or small pinches... Nothing, even moistening the snuff, helped.
Last night, I couldn't sleep so I started thinking and experimenting with new techniques and found this completely eliminates the throat hit.
I close my mouth and use my nose to draw in the air without using my lungs. I can only do a short shallow sniff (for now?) so I take smaller pinches. I learned this by taking a deep sniff using my lungs than suddenly stop breathing and continue sniffing while holding my breath.
This works so well I decided to put a toast in with my next order.