Well, using the engine to slow you down is call "Compression Braking or Engine Braking" normally used in Tractor's and known as the Jake Brake.
So Redline threw a wrench in what everyone has said about duneables. Down shift if you want, just make sure that you are going to use the power you are putting into the transmission. IE: Dropping a gear to accelerate or to get back on the pipe. You can let off the gas, it will slow you down, but don't use the engine to slow you down going down a hill?
The popular theory states, you cannot downshift a duneable. The exception is that you do not need to be at a complete stop to shift down, but you need to be in the same power ratio for your gearing. You came to the top of the hill, pulled the clutch, slowed down, you can downshift to idle speed in 2nd gear and take off from there, or whatever would be relevant to how you are riding at that time.
Also the Duneable is a better transmission than a stocker and allows MORE backloading than a stock? This I do not understand.
Adam
One question answered, and 50 new ones.