The Cleveland Browns' defensive playbook is apparently thinner than one might expect, given coach Mike Pettine's tutelage under the uber-creative Rex Ryan.

The lack of girth, Pettine told's Greg A. Bedard, is by design.

"I don't put a lot of graduate-level information in it," Pettine said. "We know in places like New England, it's only a matter of time that they somehow mysteriously end up with our playbook."

Teams guard playbooks as if the latter were the nuclear football. Players must return the playbooks before being cut, and nowadays teams can remotely wipe an iPad if a player digitally uploaded a playbook.

Still, Pettine told Bedard that at Wes Welker's wedding, Tom Brady bragged to former Jets outside linebackers coach Mike Smith (who was Welker's roommate at Texas Tech) about how the Patriots "may or may not have had possession" of a couple of Jets defensive playbooks.