[necovek]

You missed my point: where continuous dates are useful, it's ok not to care about two weeks of discrepancy even today. Basically, I am saying is that the biggest advantage of the Gregorian calendar today is its prevalance: all the other things matter less.

You also seem to be overstating the importance of exact dates when it comes to agriculture: my experience is that +-13 days does not make a practical difference, especially if it slowly accumulates (it's not like you would suddenly have to do the harvest 13 days later from one year to the next — you actuslly had to do it 10-13 days "early" once the calendar was switched, and it didn't make a difference even then).

If human civilization continued using the Julian calendar, we wouldn't have been any worse off: nothing points at it that we would have been. I am not saying that Gregorian calendar is "worse" at all (though those born on Feb 29 might beg to disagree when they go 8 years between birthdays 2096-2104 :)), just that where it's better does not matter much.