But, using your own frame of reference, you now need to convert to and fro on each cross-access. I don't really see the advantage. Notably, there is no such thing as an ontological second, it's an abstract measurement unit (loosely) bound to the rotation and revolution of the Earth. Moreover, there is no provision for such a cross-reference of basic progression of time in any Date/Time system currently available. Wouldn't be adding a constant coefficient easier? (Notably, we have modified basic constants several times, already.)