I agree, adding a purposely inaccurate output is just inviting bug reports as soon as it's released - or else causing someone problems when it returns a result they don't know is wrong. And dividing by a year length of 365.2425 just causes the year to rollover at crazy times during the day.
For example, I don't know if it's changed since Excel 2000, but it had a function 'yearfrac' that has 5 different 'basis' for returning the number of years between 2 dates. Only 1 of the 5 basis returns the correct 'age' for the pair of dates 2/29/1981 and 2/28/2008 - and that same basis doesn't report the correct age for the dates 1/31/1981 and 1/30/2008.
