On a well used coil I have seen the wick sticking out of one of the two holes. But I never saw any strands of it floating around in the liquid. I did one day think that's what I found when cleaning out my tank but it turned out to be a bit of fluff from our chocolate colored standard poodle.
With the coils that have 4 holes in it, I've really well used them but never even seen the wicks start to come out of the holes. Think maybe the holes are smaller on the coil heads that have 4 holes.