[LEAPSECS] other ignored leap conventions

[Zefram]

Steve Allen wrote:

>                Today is the second sixth day before the end of

>February, so today is leap day.


And that was obvious when days were routinely described by those
labels, today and tomorrow both being "ante diem [bis] sextum Kalends
Martius".  Nowadays it's just as obvious to the masses that --02-29
is the intercalary day, that being the day label that doesn't occur
in a regular year.  But Gregorian months suck; I prefer ISO 8601's
ordinal days.  So it's obvious to me that --366 is the intercalary day.
Potential shift of most people's birthdays, if months go out of fashion?

-zefram