Well Rolison only had one season and that was in Colorado.
I actually think their batting average with bullpen reclamation projects is probably pretty close to average. If every team claimed 10 of them a season they'd probably find 3 or 4 who were pretty decent. We've had plenty of whiffs too.
I think they're way better than average. I don't have numbers to back that up, of course. Trent Thornton? Chris Flexen? Tyson Miller? The Dodgers are a great organization, but they're not turning ham-n-eggers into significant contributors the way the Cubs do. Their forte is amateur player development. Hottovy is a real difference maker in that regard.