Thats definately an issue. But I think PW would still be productive in 3-4 years in limited circumstances. In 3-4 years would he be worth the $$$, maybe, maybe not. But this year he sure would have been.
As another example, take the Red Sox. If they had paid Pedro this offseason, they may have repeated. In 1-2 years, Pedro will be useless, unless he closes.
But sometimes you have to see the here and now, versus always planning for a future that may never come. Take you shot. We needed an uber-defense this year for JP to succeed (See Bears, Chicago). We don't have that.
Also, as a side note, we went for it in 1999, and I respect John Butler so much for that. If that play in Tennessee is called properly, its Bills-Rams in the Bowl and there's not too many of us on this board that wouldn't suffer through a couple 3-13's for just one title.