Position flexibility is more needed now than ever, in part, because teams carry so many more pitchers than they did in the past. 35 years ago a 25 man roster MIGHT carry 11 pitchers but typically was more likely to carry 10. Either 40 or 44% of the roster was pitchers. Now, with a 26 man roster teams are allowed to carry 13 pitchers and seldom carry fewer than that. Teams are forcing themselves to have more flexibility among their position players. As far as forcing Lewis to start working at other positions last year, I believe that was a product of his success when he came to the big leagues. He hit well enough that they knew they would likely need to count on his bat and his glove was not going to supplant Correa at SS last year. It's entirely possible that at some point he becomes the shortstop and Correa moves to third with Lee becoming the second baseman. OR any of a half dozen other position combinations involving other positions (and players) all over the diamond.