Harald;
What do you think about "de facto" that many technical documents
are currently using Internet Drafts as referece material?
I've seen next two cases:
1. An Internet Draft refers to another Internet Draft.
Common. It means that if the reference is normative, the I-D cannot be
published as an RFC before the other.
If both refer normatively to each other, they must be published at the same
time.
(If the reference is not normative, the draft name is replaced by "work in
progress" when the RFC is published. Then, sometimes, the draft is lost...)
2. A book refers to another Internet Draft.
Stupid, but nothing the IETF can do about it.
If you say it stupid (regardless of whether IDs are cited as work in
progress, or not), those who are publishing RFCs citing IDs (regardless
of whether IDs are cited as work in progress, or not) are stupid.
Actually, it is not stupid. Instead, it is stupid if ID editors were not
responsible for keeping records of expired IDs.
If is wise if all the expired IDs are put under:
ftp:ftp.ietf.org/expired-internet-drafts/
or somewhere else.
Masataka Ohta