Huh, never heard the grease takes out grease thing before. I'll have to try that.
I have good luck with Grandma's spot remover. Somehow I got a black stain on a quilt I had made as a Christmas gift. Ink, I guess, but no clue where it came from; a spot about the size of a thumbprint. Regular washing didn't help, SHOUT didn't help. Grandma's took it right out, no trace of it once it was gone!