I won't pretend to have watched Dunta's whole pro career closely, but he looks like a DB that needs to be playing zone with his eyes in the backfield. I would never want him manned up on anyone outside without help. At any rate, once Flowers returns, I definitely think Cooper has earned some playing time. When opponents go 3 WR, have Cooper and Smith handle the outside receivers, with Flowers in the slot.
Last 51 games for Alex Smith :
911 comp -- 1476 att -- 60% - 10,517 yds -- 73 TDs -- 3 rush TDs -- 20 INTs -- 98.7 rating