Exactly...
...now where's my Nobel Prize? Or straight-jacket?
It's a half-arsed hypothesis but I contend as decent a theory as Iapetus doing high eccentricity swing-bys and getting slashed on the Ring Plane Buzzsaw. And all the other options... heck what other options??? Anything with sufficient energy to distort Iapetus sufficiently would probably liquefy the sub-surface and so we'd see more cryo-vulcanism.
Can't wait for Cassini's up-close and personal that's coming up.
Adam