That your eye only sees 30fps doesn´t mean you can´t see the difference between 30 and 60 fps.
Analogue:
1) You´re in a room and the light is out 30 minutes (minute on, minute of) every hour and you´re allowed to open your eyes for 30 minutes.
2) You´re in a room and the light is out 30 minutes (minute on, minute of) every hour and you´re allowed to open your eyes for 60 minutes.
On average you´ll see more if the light´s on 60 minutes.







