The local beat writers suggested that Miami was simply following a league-wide trend when they decided to keep just two QBs on their roster.
But, as I recall, last season they lost both Pennington and Henne in the same game. Then, they decided to go with the wildcat in the third quarter, so they didn't have to bring in Thigpen and be unable to bring back either of the other guys. This year, the rule changed and they would have been able to bring either back.
Anyway, my point is that having 2 QBs, Schmoe Montanta and a backup who isn't very good is shortsighted IMHO. You're not even going to try and develop a guy? Really?