No, it didn't fetch a list of keys.  It performed an HTTP GET request on the bucket URI and passed a query param of ``max-keys=0`` to say don't actually return any keys to me.  You would, however, still get a response body which included the XML response with no keys enumerated within it.

This change would send a HEAD request rather than a GET.  From an HTTP perspective there should be no difference between the two except the HEAD must not include a response body.

I have never seen any documentation that states that a HEAD request is charged differently that a GET request in S3.  Are we sure that is the case?