For what I’ve read in several biographies, Steve hated to sign autographs except for maybe kids. He didn’t like to be asked if he was doing something like eating. He said the people were rude and not him by not signing. Maybe he signed this messy on purpose. I don’t know what else to think.
I've never seen a genuine one anything like this. The "M" is like one of his M styles, but that's the only characteristic I found that I've seen in other McQueens.