According to the album credits, Dre mixed Sherane, bytch Don't Kill My Vibe, Poetic Justice, good kid, Swimming Pools, Real, Compton, The Recipe, and Now or Never.
You can tell Dre mixed those tracks just by how hard-hitting they sound.
Yup, I think Dre helping make the album so bumpable is one of the more underrated roles in it being successful. GKMC bumps in the ride much better than Section.80, and S80 was my favorite album of 2011.