[lainga]

Well, for one, I think a lot of existing systems have the assumption that "this place is UTC-8 except for in this special case" and not the other way around. Also, the UTC-5 zone in North America (for instance) aligns geographically with the band of the Earth you'd get if you split it into 24 equal zones and went 5 back from Greenwich. If you went to permanent DST the bounds would all be shifted by 15 degrees of longitude.

[kadoban]

Do they really? I can never even remember which one is the "normal" time and which is offset. They're just two arbitrary adjacent offsets from UTC for me. (or really only one these days, I now live a place that skips the switch).

I'd think any technical systems also work pretty arbitrarily between the two.