Conditional GET behavior of common HTTP clients?

[Louis Theran]

Has anybody done a survey of how common HTTP clients generate
conditional GET requests?  (A quick search didn't turn up anything
interesting.)

I'm mostly interested in:

  * Whether If-None-Match is used at all

  * Whether Last-Modified timestamps are really being used as nonces

  * Whether ``Cache-Control: max-age=...'' is respected


^L