Ditto. Not sure whether or not it's a myth, but since I'm superstitious I subscribe to it.

For what it's worth, here's my routine for oil changes...
@ 1,000 miles: change oil & filter (Valvoline to vehicle spec - i.e. 5w-30 and a K&N filter)
Repeat @ 4,000 and 7,000 miles.
@ 10,000 miles: change oil & filter, using Mobil1 (again to spec) and a K&N filter.
Repeat every 5,000 miles.
Truckpoor - is that a shot of my man, Lute Olson in your avatar?
Take care,
Jerry