I'm really fascinated by such ideas. However, it's just academic as time is so much baked into physical devices (watches, clocks, ...) so this will most probably never happen.
I'd rather start redoing the calendar. It doesn't need to be metric but the different lengths of the months (and the naming Oct. should be 8 not 10?) could be reworked.
I'd rather start redoing the calendar. It doesn't need to be metric but the different lengths of the months (and the naming Oct. should be 8 not 10?) could be reworked.