There's an alternative year method, "odd + 11." When might you use it?

It's another route to the same year's doomsday; use whichever feels faster — both give identical results.

The "odd + 11" method: if YY is odd add 11, halve it, if that's odd add 11 again, take mod 7, and subtract from 7. It reaches the same answer as the 12-remainder-quarter method (for 1978 both give Tuesday). Neither is more "correct" — the 12-split tends to be easier to explain, while "odd + 11" avoids division by 12. Learn one well; know the other exists.