I've read quite a bit about fine/dry snuffs being extremely difficult to take, mainly because of its propensity to end up in your lungs. However, there's a common-sense solution to this problem. Despite that fact, I haven't seen it discussed here before. Perhaps I'm just doing a terrible job of research - if this has been mentioned elsewhere, feel free to direct me to the relevant post and lock this thread.
Simply put, this technique uses a snuff spoon to dump the tobacco directly onto the side of the nostril. Because no inhalation is required, "oversnuffing" is not a possibility.
In more detail:
Step 1: Load up the snuff spoon (or similar instrument) with your preferred dose.
Step 2: Tilt your head 90 degrees, so that your ear is nearly resting on your shoulder.
Step 3: With the spoon parallel to the ceiling, hold your breath and insert it into a nostril (this might require a flaring of the nostrils).
Step 4: Rotate the spoon inside of your nose, effectively pouring the tobacco onto the surface of the nostril.
Step 5: Pinch your nose with your fingers and apply a rubbing motion, as if you were warming a pinch of snuff. This distributes the powder over the surface of nostril.
Step 6: Resume breathing and enjoy the aroma.
From what I can gather, this is the most efficient method of taking "difficult" snuffs. However, it's likely the most unsightly as well, which makes it ill-suited for public use.