+3 will be interesting to see and all, but it generally doesn't really sway the needle. Generally the rich get richer (biggest gainers are always Walking dead, Empire, Grey's anatomy, etc). Its usually pretty comparable to the same day ratings.
Also keep in mind that the premieres are generally the high points of seasons, and once the buzz dies down, so will ratings. Theres no room left for TAR to drop. Hell, the CBS show Doubt got yanked after 2 episodes with around a .6 or .7. So we need to stay steady.