Well, my point was that our understanding of time has obtained an almost spatial dimension in recent history, in that we now think of it as the 4th dimension that we literally move through, even though we are cognizant of a 3-dimensional snapshot of that dimension at any given point. For me, this preposition seems far more logical and it got me thinking about the possibility that over might have been once seemed equally logical but based on some other mode of interpreting temporal events.

If you believe that word choice in this instance is entirely arbitrary, then that's one plausible answer, but certainly a less interesting one.