Example, couple things.
First off, Wang and Mussina were better than Schilling last yr. That isnt conjecture, that is fact.
Second off, the depth that we have comes in all varieties with all sorts of potential (to be both good or bad). Chamberlain does nothing for us this yr. Here is the list of candidates.
1. Wang
2. Mussina
3. Pettitte
4. Igawa
5. Pavano
The next 2 major league options
6. Karstens
7. Rasner
The next wave of MLB ready talent that is ready for a full season
8. Ohlendorf (180+ innings last yr, he is fully stretched out).
The future
9. Hughes
10. Clippard
11. Sanchez
The fringe
12. White
13. DeSalvo (had an abysmal yr last yr, hence why he is fringe)
Guys who could be rushed
14. Horne
15. Wright
All of the above options have played well in the lower levels of the minors and all will start at AA or higher. Note, none of them include angel reyes, ivan nova, dellin betances, ian kennedy, or joba chamberlain who all have very high ceilings.
Having depth is nice and not only do we have depth, we have depth with guys who are young. The worst part of watching a pitcher go down is watching the minor league journeyman take his place (read: Small, May, Redding, Henn, et al who took the mound in 05). Sometimes you catch lightning in a bottle but all of those options are short term, right now options. Other annoying things that come along with an injury in your rotation is when you have a minor leaguer come up who has no idea where the strike zone is. This creates heartburn and bad memories.
The one constant with all of the guys mentioned above (this does not go for Sanchez or Horne who have some bouts of control problems) is control. You get depth with guys who wont walk the park and you will get them deeper into games. This saves your bullpen. Hence, our depth gives us the worry that maybe they will get hit hard. Yet at the same time, we know we will see strikes, we know they will give us innings and it will be a look to the future rather than offering some schmuck a start here and there.
On the other hand, the sox "depth" is laughable. This is because their best pitching prospects are not ready for the show. Your best #5 pitcher will rot in long relief or even in AAA (Hansack). Tavarez is a joke on the hill and was way worse than his ERA indicated last yr. This happened with Chacon in 2005 and eventually he came back to earth. After Hansack, you have Gabbard, Snyder, and Pauley. Gabbard and Pauley walk the park and Snyder just doesnt have major league stuff anymore. This is my point. With Beckett's history, with Tavarez likelihood of folding, with Schilling and Wake's age, the depth in the rotation should have been addressed better than this. Trust me on this one. If Tim Redding (or someone of his ilk) starts a game for the sox this yr, please turn off the TV, put down the remote and walk away.