Take this with a huge grain of salt, but a guy called in to Paul Daughtery's post game show last night and reminded Paul about how he called last year to say that Homer had a shoulder injury and Paul blew him off. So he was calling back to rub it in. Supposedly this caller knew Homer's roommate.
The caller went on about how this was robbing Homer's velocity and gave Paul a big "I told you so".
Now, I realize this isn't the most reliable source, but it explains a lot of things, such as why Homer lost velocity and generally became ineffective.
Also explains why the Reds were shopping him hard last winter. I wonder if that phantom "groin" injury was really the shoulder injury..