You seem to assume that "local" is defined and does not change over time. Well I travel a lot, and my "local" could be different next month. Without timezone information I have no idea what a timestamp represents.

>You seem to assume that "local" is defined and does not change over time.

On the contrary, what I'm saying is that we need to be able to store date/time specifications that do not (yet) identify a point in time. Of course we also need to be able to store actual points in time.

"Local" is a pretty vague term. I can refer to a specific place or to an as yet unknown place.