I was reading an earlier thread from Iron Frank about grinding your own cinnamon, and seem to recall that most commonly available stick cinnamon is from a less flavorful part of the plant (or perhaps from another plant entirely, like cassia). Perhaps I learned that at The Spice House in Evanston, IL -- link attached.
Has anyone else heard this? If that's the case, save your coffee grinder's blades and buy small amounts of the ground stuff.
I'll add that The Spice House's Vietnamese cinnamon (available in this country only in the last few years) is a wholly different, wonderful, complex spice, far more interesting and flavorful than anything found on supermarket shelves.