slincoln
Isn't there some software and/or device out there that allows one to play alone and it tells you how accurate your meter is? I saw something a while back, it was made for drummers. Hopefully, they expanded it for other instruments, as well.
Most electronic drum brains incorporate such a thing.
I have a slightly different take to the original question; because it's bloody hard to hear the click track when playing drums! :-D Granted, in theory, you should be able to hear the first few clicks then play from that moment on and keep perfect time indefinitely without subsequent reference to the click track. But how many people can do that? And not just drummers. How many guitarists can start playing after hearing a few beats and still be perfectly in time minutes later if they have not heard the beat or click for that time? Try it yourselves, possibly with the help of a friend.
Richard Feynman discovered that most people can keep accurate wonky time. He could quite accurately measure a minute, but only by counting 48 'Feynman seconds', not 60 'click track' seconds. Dunno if that's entirely relevant but I found it interesting. He also discovered that different people internalised time keeping differently; he found he could read whilst counting a minute, but not talk. A friend could not read but could talk:
https://www.youtube.com/watch?v=Cj4y0EUlU-Y It may be, therefore, that some people have trouble with following a click track because their internal 'time representation engine' which they would need to follow the click track is already in-use trying to keep their own time. Others, who use a different internal representation, may more easily be able to separate their own internal time keeping from following the click track. Because of this, perhaps some would find it easier to follow a flashing light rather than a click sound, whereas for others this would be very difficult.