[time-nuts] Is there an application for time-stamping with absolute time?

[Erik Kaashoek]

Just because it was possible I added time-stamping with absolute time to my
timer/counter. But now I am curious on what to do with this ability.
Are there any applications for this? And if so, any specific requirements?
I can imagine it could be used it to check if the seconds tick of a
mechanical clock is on time but I have never done such a measurement.
And a second question, is there any standard time format to be used for
such and absolute time stamp?
It can be date and time with a lot of digits after the coma for the seconds
Erik