Yes, they have subtracted. They have also improved in some areas that you are conveniently leaving out.
#1- their SP was very good last yr and that was with CC struggling with bone chips in the elbow and Pettitte only making 12 starts (freak ankle injury and started the season late). They also saw a big step forward for Phil Hughes, who put up better numbers than the annointed one (Buchholz) but is somehow expected to involute into a firebomb and die. We also saw David Phelps emerge as a true big league rotation candidate. We saw Ivan Nova take 1 step forward in learning how to set up and put away hitters, and 2 steps back in that he threw less strikes and gave up more HRs. Yes, their SP are a year older, that being said, our geriatric club started 45 games last yr. I say that it is highly, highly likely we see them start more than that. Add in a second yr for Phelps, a contract yr for Hughes, and a fully healthy season from CC and I dont think it is even close in terms of SP.
#2- their RP was very good last yr, and we lose Soriano but gain a healthy Mariano. Say what you want about Rivera, he was heading for another standard Mo season last yr before he blew out his knee. His arm should be fine. Throw in a healthy yr from Joba, who finally started looking like his old self towards the end of the yr as well as a healthy yr from Aardsma, another full yr from Robertson and Logan and the cadre of pen arms behind him, the Yankee pen will be formidable again. The biggest reason why their pen will be formidable is the fact that they will get a ton of innings out of their SP. Last yr, only Seattle and the Bombers had their starters eclipse 1000IP. With a full yr of Pettitte on the horizon, that looks more likely than not.
#3- the offense will take a small step back without Swisher. We brought in Ichiro which won't completely offset the offensive loss, but defensively and speed wise, we upgrade significantly. And for those who forgot, we will have a healthy Brett Gardner back in the lineup. You know, the guy who had 10.7WAR from 10-11 but missed all but 16 games in 2012. Youkilis should be able to replace the ARod we had last yr. Obviously, he cannot replace the ARod during his prime, but last yr's ARod had an OPS of .782. Once Youk got out of the poisonous Boston environment, he put up an OPS of .771. Jeter is coming off ankle surgery, which is a concern. It'd be even more of a concern if he was still limited. Well, he isnt. The guy is back on the field performing his normal baseball activities. While I doubt he can sustain a .300+AVG, he should be good enough for above average production for the entire yr, as usual. We should also see improvements from Granderson. You brought up Martin, but he was a terrible hitter for most of the yr. He had some power and walked a good amount, but his OPS was barely over .700 and it was driven almost entirely by his HRs. We can replace the defense with Romine, and we shouldnt see too much of a slide offensively since there wasnt far to go in a downward trajectory. Overall, I expect the offense to put up 800+ runs like it always does. I think the sox offense will be in that vicinity too, although they're not nearly as complete as you think they are.
Overall, our pen can keep up with yours because they wont be overworked and have the personnel to go head to head, our offense should be a tick better than yours, and our starters are head, shoulders, knees and toes better. It aint close