I think, that he's seriously suggesting that we find a unit of time that can be guaranteed to just increment and not be subject to leap stuff or calendar adjustments and can go forward and backwards in time as simple increments and decrements.
I have sympathy for this view. Back when I was doing time & date stuff I worked out a decimal calendar as a thought experiment. If you are happy to drop the idea that a "day" has to align with a period of daylight, and/or the "year" has anything to do with seasons then it's pretty easy...