From 1957 until 1989, for 33 years, the Finals had either Boston or the Lakers, or both, just about every single year. Only 6 times, out of 33, were they both shut out. The Celtics went 16-3 in their 19 appearances, and the Lakers went 6-12 in their 19 appearances... but 8 of those losses were to Boston... and 2 of the 3 Boston losses were to LA (1985, 1987)
correction