Joe Johnson and Gerald Wallace have the honor of taking the majority of Brooklyn’s most difficult defensive marks, and there’s enough cross-matching potential with C.J. Watson and Deron Williams to shield Stackhouse and Bogans from opponents who would capitalize heavily on their declining athleticism. Whereas Brooks loses his way on an incredibly regular basis, Stackhouse and Bogans at least have their defensive bearings about them — an trait which Johnson obviously puts at a premium, even relative to Brooks’ bucket-getting potential.
Mahoney's assessment is spot-on; MarShon Brooks is a porous defensive player, and Stackhouse's value as a spot-up master playing off talented creators beats Brooks' ability to replicate Joe Johnson and Deron Williams to a lesser degree. Even with Brooks' offensive wizardry, the team's offense has struggled with him on the floor, scoring just 95 points per 100 possessions (the worst of any rotation player)
I have faith in Brooks as a Bench Mob scorer if he can get consistent minutes, but as long as Coach Johnson plays Joe Johnson as the Bench Mob scorer, there's not much space for Brooks in the rotation just yet.