His O-line is worse this year than last year. As for everything else you mentioned, NO, Pennington did NOT have a much better arm before his injury. One of the biggest things about Pennington has been that he was ALWAYS called noodle arm. He's never had great arm strength. And last year was the 1st year he was ever not injured.
As for his ankle, how do you think that happened? OH, yeah, that's right, Green (or whomever it was) got by the Left Guard to hit Pennington. As I said, the Jets O-line is a big issue and its worse this year than last year because of how Mangini / Tannenbaum handled the Pete Kendall issue.