[Exim] require verify = header_syntax

Has anyone here tried using require verify = header_syntax on a system
with lots of users? If you found that the test has too many false
positives, do you have any opinions on how it could be modified to create
a slightly more lenient version that is usable in practise?

I've been experimenting with it and many problematic rejections are caused
by (in terms of RFC 2822 syntax) display-names with dots in, or which are
in the form of an addr-spec.

--
Tony Finch <dot@???> http://dotat.at/