Re: So, after the Hamilton trade ...
I've always thought that lefty screwballers were very interesting: there's Carl Hubbell, Tug McGraw, and Fernando Valenzuela. Jamie Moyer and John Franco have exceptional screwie changups. Spahn added a screwball late in his career, with great sucess.
Most threw a lot harder than Daniel Herrera. Color me intrigued, though. He's my new favorite minor leaguer.