[karmakaze]

Different than the UTC/TAI issue: A limitation of only using UTC timestamps came up when I worked at a social photo sharing company. We needed to define how to store and transport them, and everyone was saying UTC is the answer and I was arguing for local time + TZ and/or location.

The example I used was if New Years pictures were posted by a photographer in say New Zealand that was being viewed by someone in the US. Showing the US local time for that photo doesn't indicate how many minutes before or after midnight the photo was actually taken. For data transfer, ended up using strings for local date/time and location to ensure that nothing tried to interpret and transform unless explicitly intended.