On Tue, 10 Sep 2013, Daniel Kahn Gillmor <dkg@fifthhorseman.net> wrote:
> On 09/10/2013 06:35 PM, Austin Clements wrote:
>
>> I haven't looked at exactly what workarounds this enables, but if it's
>> what I'm guessing (RFC 2047 escapes in the middle of RFC 2822 text
>> tokens), are there really subject lines that this will misinterpret
>> that weren't obviously crafted to break the workaround?  
>
> not to get all meta, but i imagine subject lines that refer an example
> of this particular issue (e.g. when talking about RFC 2047) will break
> ;)  I'm trying one variant here.

That's cheating.  ]:--8) Though, I wonder, you mentioned in your
original email that there would be subject lines that are
*unrepresentable* given the worked-around RFC 2047.  Did you mean that?
If so, can you provide an example?  Isn't it always possible to, say,
RFC 2047 escape the whole subject, which would be decoded correctly
whether the decoder strictly adheres to RFC 2047 or uses the
workarounds?

(Speaking of which, it looks like message-mode does *not* RFC 2047
encode the subject if it contains text that could be mistaken for an
encoded-word, so such subjects won't get round-tripped correctly.)