Stephen Colebourne wrote:
I think what Jon is asking, and I'm confirming, is that this data *should* be considered part of the public data exposed by the tzdb project.
When I wrote that data, I didn't worry about the DST-vs-STD offset. I cared only about the correctness of the sum of the offset and standard time, because I knew that only the sum mattered. At this point it would be a nontrivial project to verify that these offsets actually make sense everywhere in tzdata. (They usually do, but in some cases I vaguely recall that there were issues.) Until such a project is done (and I'm not volunteering :-) it would be misleading to document that the offsets are meaningful. There are many ways in which tzdata source code can differ in appearance while meaning the same thing. For example, although a time can be written "1:00" or "01:00" or "1:00:00" or "+1:00", none of this matters in zic output. This sort of thing is intended to be obvious, but unfortunately it was not obvious in this case.