If you are coupled to a rock in the sense of always having it readily available, use it a lot, trust it implicitly, and so forth, Clark infers that the rock constitutes a part of your memory store." (Adams and Aizawa, 2010, p. 68).Now, I still think this is kind of funny, but alas not correct. Insofar as a rock is typically not an information resource, then by Clark's lights it's not something into which cognition can extend. I've mentioned in a couple of posts already that it's Clark's view that cognition only extends into information resources. I like using the recipe versus the oven story in baking a cake to make the point.
Nevertheless, I think that the principal point we were driving at is still correct. One cannot extend cognitive processing into an information resource just by being coupled to it in a "trust and glue" kind of way.
Defending the Bounds of Cognition (with Fred Adams). (2010) In Menary, R., (Ed.). The Extended Mind, Cambridge, MA: MIT Press. (pp. 67-89).