Plummer has had a 4000 yard season. Fiedler, Lucas, Rosenfels, (Brian) Griese, Feeley, Shane Matthews, Jim Miller, Henry Burris, Chris Chandler, Cory Sauter, Rex Grossman, Cade McNown, and Kordell Stewart never have. I believe that's the exhaustive list of QBs Chambers and Booker have played with, btw.
That brings up another point -- in 2001 when Boston had his monster year, Plummer threw EVERY pass. Neither Booker nor Chambers have had that stability over a season at any point in their career. That's huge.
As to Boston being all of Arizona's offense, it hurts the case for Chambers. It really doesn't for Booker. Des White and Anthony Thomas in 2002 for the Bears are equivalent to the duo of Frank Sanders and Michael Pittman in 2001 for the Cardinals.