It's not clear to me that there's consensus that anything qualifies as Best
Current. We have some small samples of a few things that some people have
tried, but I don't sense we're there yet.
I hope that lists signing their outbound mail qualifies. Large
providers Googlegroups and Yahoogroups do it, small providers
including MAAWG and myself also do.
Beyond that, you're right, we're at best guessing and at worst pulling
stuff out of our whatevers.
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