Again, you're assuming that the demand for Cassel will be the same in 2010 as it would be in 2009. There is a lot of evidence (see the QBs that will be coming out in the draft in 2010) to suggest otherwise.
Also, if the Pats don't trade him, they will almost certainly seek to extend him long-term, so they don't have to carry a $15M cap for the entire year.
And those rookies are risking injury playing in college this season too - so I guess they should be coming out in the draft this year, no?
Technically the entire NFL could disband - a comet could hit the earth - lots of "risk"
But in a football sense, Cassel's value, in another season with NFL inflation and the potential for an uncapped year is going to at best increase his value - even against a rookie who, with not one NFL snap under his belt who is going to command the same amount of money.
Asante Samuel's a good case in point - and he actually WAS risking a lot because he played a full season - potential injury and potential poor performance could have hurt his value. But it didn't - and he got significantly more money in the first two years (Tagged year and first year of his contract plus all guranteed) than he would have if he JUST took the first two years of his new contract.
Iggles Blog - Philadelphia Eagles Blog: Asante Samuel's Contract
See for yourself.
Asante got $8 million in 2007 plus $20 million guranteed by signing with the Eagles in 2008.
That's $28 million over 2 years.
Had he not been tagged and signed a year earlier (at what would probably be lower 2007 NFL dollars) he'd be looking at only the $20 million (well more like $23 counting salary - but that's still less than $28)
Again - the difference here is that Asante risked a lot - but was rewarded with more. In Cassel's case with Brady playing he wouldn't be risking injury, or poor performance... AND he'd potentially be looking to sign a contract in an uncapped year. AND Cassel is getting considerably more than Samuel did as a tagged player.
Keep in mind that unless Samuel was an idiot, he took out a pretty good insurance policy to pay him nearly all he'd make on a new contract in case of injury. That's money well spent, and I don't know why anyone thinks Cassel wouldn't do the same.
I think we're all in a "hypothetical" mode now that it appears that regardless of Bill's comments they are attempting to trade Cassel now - but I wouldn't agree that they would extend him long term this season to lessen his cap hit. That doesn't make sense to me at all.