I have 2x Titan X and a 5960x and playing at 1440p I get at least 60 FPS (80-90+ in much of the city) most of the time even in the countryside except for the occasional situations it drops to the 50s or even high 40s. I get occasional stuttering but I have a gsync monitor that covers up most of that and makes the worst drops more bearable, but still...
I have almost everything maxed except AA; I only have FXAA enabled right now. It's not ideal. I'm wondering what else I could do here that would make a significant enough impact to keep me above 60 fps without sacrificing too much.
As you and others have shown you will get dips no matter what. Short of much better hardware or more optimization sacrificing too much seems counter productive considering that fact. You can have fidelity and 60fps what most of us want is fidelity and locked 60fps.