Dude.
RM needs to make this canon in the Dwarven Race description for Battle Biscuits(tm)!
They could add a recipe with forge scraps, grit from a mithril ore vein, and hobnails from a worn armoured boot!
OK, that seems a little extreme. LOL It was meant to be the dwarfen equivalent of Civil War hard tack. It was supposed to be food, it was meant to be eaten, but the troops used it for other stuff. And only dwarfs can actually consume it if they were ever desperate enough to eat it.
* - I do like the thought of one of my ideas becoming RM canon! With or without the (tm)