This is, in fact, erroneous. The conditional GET mechanism exists
to allow efficient cache updates -- why the cache is updated is up
to the cache manager. It is *not* broken if it chooses to service a
request from its cache, unless there are clear instructions in the
request or in the cached message indicating that it should not do so.
....Roy T. Fielding Department of ICS, University of California, Irvine USA
Visiting Scholar, MIT/LCS + World-Wide Web Consortium
(fielding@w3.org) (fielding@ics.uci.edu)