Any renderer which isn't CPU (read: driver) bound doesn't take performance seriously or hasn't been optimized yet. (Not that that refutes what you're saying, I

Any renderer which isn't CPU (read: driver) bound doesn't take performance seriously or hasn't been optimized yet. (Not that that refutes what you're saying, I'm just saying that most serious engines are in the same category as BF4 when it comes to gains from better driver APIs)