Wow. Sort of a the typical textbook Cobb! I'm not a Cobb guy, but it certainly has enough of the right look and vibe, amount of uneven ink aging/coloration, to me that if I came across it at a reasonable price, I'd take the chance. Paper, ink, flow, structure, it all looks plausible to me; like written by someone who's penned it his whole life.
I'm not the best on Ty Cobb, but I don't think think he signed this. It's signed too slowly most of all, with little variation in pen pressure, and has a number of uncommon characteristics. Cobb generally signed quickly.