I guess I just kind of disagree with the logic. Even the best lineups, if you can improve it, will help improve your team overall, even if it doesn't address your weaknesses. It's like a team with 4 aces and a #5 in their rotation. They sure don't need another ace, but they still get a lot better if they get one. Boston's only concern should be how much better they get at catcher with Lucroy than Vasquez, and the answer is a lot. It's about as massive of an upgrade as they can make without improving the rotation. There's a good article that illustrates my point up in post 105. Junior Guerra might be an interesting add-on for extra value packaged with Lucroy to Boston.