> The "Received" header is woefully inadequate for spam tracing
True. Then again, so is the rest of the message format and mail
transport.
I don't agree it's "woefully inadequate."
In the realm of anti-spam, the typical approach to discussion seems to be
first to declare that some portion of the system is woefully inadequate, and
then to propose a new and wonderful solution. The 'then' clause is often
omitted.
So...
When we have some agreement on the information that is needed to facilitate
spam tracing, then we can decide whether it is better to add it to Received or
create a new header.
d/