Sometimes "strength" is as much illusion as reality. Consider the Red Sox starting rotation.
The "strength" argument looks at Lester, Lackey, Buchholz, Peavey, Doubront, and Dempster...with contenders like Brandon Workman (serious) and Allen Webster (are you serious?).
Lester and Lackey are legit and I'm a Doubront fan, although his pitch efficiency (ability or willingness to pitch to contract) is an issue. Peavey is at least healthy, but Buchholz's 2013 can't be viewed (healthwise) as confidence inspiring and Dempster gives you more innings than high production.
Yes, you can win with an E.R.A. approaching 5, as long as you lead the league in both on base percentage and runs scored, which is not assured.
As for Anthony Ranaudo, Matt Barnes, and Henry Owens, you cannot expect to catch lightning in a bottle, no matter how tall the bottle. While all could pitch next season in Boston, we simply can't expect more than stopgap production.
The Red Sox principal advantage over (for example) the Yankees is pitching. The Yankee bullpen is in rebuild mode with the Rivera retirement, and their current starting rotation is Sabathia, Kuroda, Nova, Pineda (coming off injury), and presumably a (luxury tax eating) free agent. Manny Banuelos is coming off surgery and Dellin Betances has a live arm and low H/IP ratio speaking to his potential. Nova pitched only 139 innings last season but certainly has an upward trajectory.
Never underestimate the need for quality starting pitching, no matter what you think.
Money can't play.