* in Accept-*

[mnot]

* in Accept, Accept-Charset and Accept-Encoding request headers is of very limited use, because:

• With a qvalue higher than another value, it says "send anything in preference to something specific", which isn't useful
• With a qvalue lower than another media type, it says "send a more specific value in preference to something else", which is already implied by HTTP
• With a qvalue of 0, it says "don't ever send other value" -- but a server can always ignore that, because this is an optional-to-implement extension
• In media types (e.g., text/*), it has been cargo culted a lot, but doesn't actually give the server information it can use.

Can we deprecate * in these headers, or at least restrict its use / give better guidance?

[mnot]

Discussed in Montreal; support for documenting limitations / caveats.

[royfielding]

We can't deprecate it. We can explain when and where it isn't useful.