The Yanks have 3-4 top pitching prospects. If you can get one of the best first basemen in the game for one of them, I would say you certainly do it.
Exactly, we have 3 or 4, so give up a different one. He is the #1 pitching prospect of all those top pitching prospects. His 95-98 mph fastball and devestating slider rival that of Randy Johnson, although he is obviously shorter and right handed. Then when he throws in that nasty curve and developing change...wow. Give me all of that over Teixeira's 40 home runs. As I said, deal a different pitching prospect. Give them Kennedy, give them Clippard, I don't care who...but do not give them Joba.
Even if guys dominate AA ball, they still have a long way to go to translate that into MLB success. Sure, chances are they make it, but they are not a sure thing. A guy like Tex is as close to a sure thing as you will get.
Of course he has ways to go, but AA is the toughest level in the minors. While Tex is as close to a sure thing as you will get, Joba is as close to a sure thing in terms of pitching prospects as you will get (similar to how Hughes was in AA).
You fail to take into account that trades are also based on team needs. The Sox don't really need Helton, the Yanks desperately need a first baseman though. Sure, everyone needs pitching, but those prospects are a while away - that first baseman is there though (although he doesn't seem to be on the market atm).
HA! If anyone fails to take into account team needs, it is you. What we need most is pitching, and even more than that is YOUNG pitching. We have a chance to have a top 3 of Hughes-Chamberlain-Wang next season and for a decade after that...find me a top 3 better than that. I'll take Douggie M's defense and out 5.5 runs a game to go along with that pitching. Or we can always sign a power hitter in the offseason. Regardless, I can tell you that we are not going to find a 22 year old fireballer on the free agent market any time soon.
I am not discounting Chamberlain, he definitely is a good prospect. But he is a P R O S P E C T. He is more likely to succeed than Random Pitcher X, but he is not a sure thing.
He is more than just "a" prospect, he has a great chance of being the top pitching prospect in baseball to start next season (if he isn't in the majors already). This isn't a guy in low A ball who is strictly potential (such as Betances), he is no longer a guy based on projection, it is no longer about "if" he can do this or that. He can be in the majors by September. You make it sound as if he is 2-3 years away and he is all hype and hope.
Like I've said 5 times, it is not that I am against trading pitching prospects, just not great ones. I'll give them Kennedy AND Clippard AND Eric Duncan, I don't care. But they are not getting their hands on Joba.
Also, you still have failed to give me reasons as to why Joba can't be an ace or why he should be dealt. Your only reason is that he is a "prospect," which isn't a good enough reason for any owner around baseball.