Maybe Jim could provide some guidance on this one.  I'm guessing he is probably one of the few preparers here that would be keeping track of his day by the second.  As for myself I am still old school.  I scribble down on a post-it pad what time I start and "punch out" when I get side tracked on something else and sign back in on the post-it when I am hunkered back down.  I would keep track by the second, but the time it takes to write down the seconds is a second or two I could use to actually prepare the return 😁