You don't think he could have gotten less total money but more guaranteed from the Steelers. He overplayed his card. He thought being an RB was as important as WR. (See what Brown was able to get).
Some stuff about the Steelers contract.
According to NFL.com's Ian Rapoport, the contract included $33 million in guaranteed money, which was going to be paid out over the first two years.
Now his guarantees with the Jets contracts aren't really that much higher. He gets 27m guaranteed in a 4 year vs 33m guaranteed in a 5 year.
The issue was evaluation the entire time. He thought he could get 17m a year with more guaranteed. But he didn't at all.