MIME type override query

Regarding Issue contentTypeOverride-24 and ACTION-233,

Minutes from the IETF/HTML liaison meeting in March:
  http://esw.w3.org/topic/IETF_HTML5_Meeting_March_2009

And in particular, the topic of "content sniffing" has started a lively discussion on the HTTP working group mailing list:

http://lists.w3.org/Archives/Public/ietf-http-wg/2009AprJun/

I think the discussion seems to recapitulate some of the same arguments about "error handling"


 1.  Originally, the web required (or should have required) sites to follow spec A (senders may send A, receivers must read/interpret A).
 2.  the sites didn't do that, they instead exhibited  behavior A'  (including some things that aren't A compliant)
 3.  Browsers changed to accept A'
 4.  Now, some want to change the A standard to describe A' as the standard
 5.  Others believe that A' should (continue to) be forbidden

I think this applies to content type sniffing (A = content-type must match, A' = some content types are determined by sniffing).

I think the arguments have to deal with legacy content and controlling future behavior:


 *   There is lots of A' around, and it is impossible to ever changing that, so A' is "reality".
 *   There isn't much A' around, the sites that do it are broken, and a lots of browsers giving errors on A' but accepting A will cause A' to go away
 *   Economic forces are such that browsers won't refuse A' - it's not in their interest, people might use other browsers instead


I think this applies to content-type sniffing, mis-nested tags and a few other "error handling" cases.



Larry
--
http://larry.masinter.net