From your link:
Update: Here’s a fact sheet being circulated by Romney’s campaign. There’s little question George Romney was sympathetic to the civil rights movement and publicly known to be so. There’s also little question, it seems, that he never did actually march alongside MLK (although he marched at events sponsored by him).
I think we are almost all in agreement that the facts as we now know them are that elder Romney did NOT actually march in the same march as MLK marched in.
The issue is whether that is a revelation to ALL of us, or if SOME of us knew that all along and were lying about it.
It seems clear to me that everybody in this story believed it, that nobody was lying about it, and it was just a case of mistaken memory.