I thought the shortcut text was derived from what bindings are, and not necessarily from InputGestureText property. Perhaps a long time since I did this, or poor research on my part (sorry about that). I don't know just providing the text will acutally allow the bindings to work. Perhaps I need to do a bit of implementation to get the bindings working properly, even if displaying the shortcut is easily achieved.
I am currently working on something else, so i will have to follow up on this when I get back to this task again.