First of all, this is the first time Wallace ever quit. Taking himself out of a meaningless game, AFTER the team was eliminated from the playoffs so this isn't "quitting" much, to protect himself. He's already earned his payday. Unlike Keenan Lewis.
Which brings me to my second point. If the player doesn't seek out the trainers, it's not on Tomlin to send them to the player.
And about the aging defense, Timmons (2007), Lewis (2009) and Allen (2011), were three of the most important players on the #1 defense in yards and would be higher in points if not for turnovers by the offense.
Anyway, go Browns.
you list 3 players.... its an 11 man defense. i feel so comfortable we are "secure" with these 3 players and the one hasnt been a starter till late in the year