[tz] [PATCH 2/3] Replace some zones with links when that doesn't lose non-LMT info.

[Paul Eggert]

On 09/03/2013 01:10 PM, Lester Caine wrote:

> I see no reason we should not have the same confidence with most of
Europe?

Wars are one reason.  For example, the current TZ database
"works" for Mulhouse, France only because it excludes zones
that differ only before 1970, which means we currently don't
care that many pre-1970 timestamps are wrong for Mulhouse.
If we moved the fencepost back to 1900 we could add a zone
for Mulhouse, but we shouldn't use the Shanks data for
Mulhouse, because it's obviously wrong (I just checked).

Maybe someone could do the legwork to research Mulhouse
thoroughly, as we've already researched Paris.  But maybe
not; and even if Mulhouse is doable there must be hundreds
of other locations within France that would need the same
level of research, where the Shanks data are wrong or are
almost surely wrong

Doing all this properly would be a lot of work, and I expect
it would be a mistake if we simply tried to shoehorn the
result into the current tz database format.  I don't have a
solution here; I'm merely noting the problem.

> So some indication of what IS 'woolly'

That indication is currently in the comments.  I suppose it
could be automated more, but that also sounds like a lot of
work, work that I hope someone else does and not me.  You
could start by assuming that the pre-1970 data are unreliable
unless supported by a source in the comments, where
Shanks and Whitman do not count as reliable sources.