I always thought Coleman would start in front of him, with a heavy rotation, with Spears eventually being worked in as a starter as you got into October. Canty is a rookie as well, coming off of a major injury.
And just because Spears can watch practice and drills doesn't really mean much. His position is not cerebral. His "learning curve" consists of muscle memory more than anything, and that comes through repitition. You can read a book on your golf swing, but you're not going to swing the club with any success until you get out on the driving range and start putting it into practice.