I just received this tip from a friend:
Some VCR and other relative bad RTC units will show a wrong day of the
week starting at January 1st 2000, so to avoid problems when programming
the unit (day of the week vs day of the month), just change the year to
1972, so it will still compatible to what *should* be in 2000, and the
following years will follow it correctly, 1973 = 2001, and so on.