[tz] [PATCH 2/4] Move obsolescent Americas entries to 'backward'.

Paul Eggert eggert at cs.ucla.edu
Wed Aug 28 15:25:35 UTC 2013

Lester Caine wrote:
> a large number of us are using genealogical databases

Sure, but that's always been outside the scope of the tz project.
As the Theory file notes:

  the database is not designed for and does not suffice for
  applications requiring accurate handling of all past times everywhere,
  as it would take far too much effort and guesswork to record all
  details of pre-1970 civil timekeeping.

That being said, it might be helpful to have a new file,
"attic" say, that records discarded Zone data that may be
useful to genealogists.  If a genealogy-oriented extension
to the tz database ever becomes a reality, it could take over
the attic.  If there's interest in this, I'll propose a new
change along these lines.

> and need to know that we are working with the same numbers

If you have the same version of the tz database, you'll know that;
conversely, if you have differing versions of the tz database, you
cannot rely on that.  This has always been true, and the proposed
changes don't alter this property.

Stephen Colebourne wrote:

> Changing something because it is "neater" or general
> "tidying up" are bad goals

I too was reluctant to make the change.  But the motivation is
not "neatness" or "tidying up": it is to avoid future political
brouhahas like the ones we've had recently, brouhahas that consume
far too much of our time.  Avoiding these disputes requires fairness
(what you're calling "tidying up"), and fairness is not an
easily-omittable triviality.

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