I've reconsidered my previous position.
I'd like to see those pitchers as our top 5 in 2008.
'Whither Joba?' you may ask.
I propose using him like the 6th man on a basketball team. Let him pitch once a week, rotating between slot 3, 4, and 5. The odd man out of the rotation gets skipped for that turn in the rotation and becomes the long man in the pen. Using the 6th starter as a long man saves the Yankees the roster spot that would otherwise be wasted a Rasner/Igawa/Karstens.
A regular starter will make 32 starts over the course of a year. This 4 man/3 slot approach would hold each player down to 24 starts (about 150-160 innings each, depending how much they were used out of the pen).
If someone gets hurt, tired, ineffective, or throws a hissy fit then his replacement is already on the 25 man roster.