That's been true historically, but historically, he's been right. Two guys that come to mind immediately:
Colon
McDowell
both wanted huge contracts (or huger than we would offer), didn't get them, got out of town, and promptly sucked.
The guy we did give the huge contract to was Navarro.
If you take a look back, I'll think you'll find that JR has been vindicated in not offering the huge contract.