I'm right there with you on that fence. I have heard that story, but would have to look at a lot more IP examples to know if this is truly the case. Right now, I'm leaning towards the TTM being the real deal.
True. More of a risk today than it was in, say, the late 1970's, when Joe Dimaggio's sister would sign for him. Back then ghost signing was practically unheard of. Today, usually all you would need to do to assess whether or not something is authentic is to compare authenticated examples with a TTM.