I generally do not pay much attention to stories coming out of spring training because 90% of them follow the same pattern: Player X is in great shape, Player X is focused, and Player X spent the offseason doing [insert good activity] to prevent a recurrence of [insert bad thing that can happen to a baseball player, like injuries or hitting .220]. That said, the stories about Tommy Hanson's new delivery are interesting to me because it's not every day that a player as successful as Hanson undergoes a fairly radical change. Hanson has compiled a 3.28 ERA in 460 big league innings. His career ERA+ is 120, which is good, especially when you consider that it is pulled down by his bad five-start stretch at the end of his 2011, when his ERA ballooned from 2.44 to 3.60 before he was shut down for the year. The injury that ended Hanson's led to the changed delivery; his performance did not require a change.
Derek Carty at the Baseball Prospectus provides the pessimistic scenario ($) for Hanson's new delivery:
Altering a pitcher’s mechanics is a risky move. When I went to scout school, the instructors always advised caution when dealing with a pitcher who had made more than a minor tweak to his mechanics. You see, if a pitcher is throwing with the same mechanics through high school (or earlier) and into his major-league career, he has repeated that delivery tens of thousands of times. His muscles have developed around that delivery, and they’ve been strengthened based on the particular movements he makes. If you go and change a guy’s delivery in a non-minor way, other muscles that haven’t been evenly developed may now be relied upon more heavily. Pitching is an unnatural motion to begin with and places extreme stress on the body, so pitchers are going to get injured no matter what, but when those muscles lag behind and are suddenly being called upon to play a major role in such a violent motion, the theory postulates, a pitcher becomes even more susceptible to injury.
Unfortunately, that makes a lot of sense to me. Hanson has presumably used his old style of delivery for most or all of his pitching career. Now, we are expecting him to learn a totally new way to throw in one offseason? Even if he remains as effective as he was last year, we will all have Carty's point in the backs of our minds: when is the inevitable spillover injury coming?
In that respect, Hanson's season is going to be like that of the entire Braves team. With the specter of last September still hanging over the team, we are going to have a certain sense of dread even if the team starts out strong and remains in a playoff spot throughout the summer. Maybe that sense will go away once the season starts and washes out the last taste in our mouths, but given the historic nature of the Braves' collapse last year, I doubt it.