You'll note I used the word "autobiography" in quotes. Not the most reliable source of information, of course. It would seem to have a vague ring of truth about it. While with Charlie Parker, Miles had written 'Donna Lee' although it got credited to Bird. According to John Szwed in 'So What' "On the advice of his father, Davis registered the composition [of Boplicity] under his mother's maiden name, to make sure his rights were protected."
Here's another question that's always bugged me... who wrote 'Nardis'? Again, Miles got the credit... I seem to recall someone somewhere saying that Miles got the tune from 'some dead guy'. Wish I could remember where I saw that quote. Anyway, beautiful tune.