Signatures these days are more in the "legal mark" department than "legible cursive."
For the last decade and a half mine has been a defined set of swirls with one legible character. I've had fits of legibility now and then, but they still involved artistic license and a dogged refusal to have a surname.
I think if I were to acquire a surname I liked, when practicing my new signature I'd add in more legibility.
Back to my question, what I'm hearing is that signed copies won't be available right off, unless someone hits up your signing then ebays it.