How successful are submarine pitchers?

several have been succesful as relief pitchers in the bigs. There are currently a handful- Jeff Nelson has been a reliable set up guy that comes to mind. My fav and probably the most sucessful was Dan Quisenberry of the Royals. If you submarine, expect to be a reliever though- and the key is to learn to throw in multiple arm slots- it changes to way your pitches will move. Best of luck