I think it might be helpful if we advocate that breadcrumbs (or any other pattern) be used for one form of navigation. The conceptual function of breadcrumbs is to remember which of the many possible turns I took to get here. Where's as a wizard guides me along a single, linear path with several stops along the way. The same goes for undo history.

So breadcrumbs are useful for navigating complex, n-deep content structures/information hierarchies (many possible turns). A wizard is really just a traversal of a flat content structure; a sequence of steps, the history for which is similarly flat. The same goes for undo history. I think there are many of other patterns we can appeal to for efficient navigation of such flat content structures without re-purposing the breadcrumb pattern for multiple functions. I think it might muddle the behavioral model associated with the pattern if we do.

Hope this helps!

Ken and Andrew, you convinced me to keep the guideline as it is.
I added the nice reference to n-deep content