The problem isn't if people can see flicker from 10 or 16ms refresh rates. The problem is mainly if people can see the intermodulation when a LED display with instant turn on/off is near another light source that also flickers at a frequency not too far from the display frequency. Low-frequency incandecent tubes are flickering a lot and a big source for intermodulation effects.

If you walk and at the same time look at a 60Hz or 70Hz CRT in a room with normal low-frequency incandecent tubes, you can clearly see the CRT monitor flicker. If you stand still, the problem will decrease and if you stand still in a dark room you will probably not see any flicker in the monitor.

A similar effect (but for sound) is when you have two 7200RPM disks that are running with a slight difference in rotational speed. The intermodulation may be very noticeable and disturbing.

Another thing to think about is the amount of "italic" you get when you scroll text horisontally and drives the individual scan lines one-by-one. Your eye will see skewed characters - the faster refresh rate, the less skewed the characters will look.