The issue was that some people would move wires from one cap to another while swapping distributors thinking that the caps/clips were the same orientation/position on dual and single point distributors, and might not look at the rotor position relative to the wire position, but just go by the position of the wires based on the clip position, like when you are doing a tuneup and just changing a cap and want to put the wires back in the same holes as they were in on the old cap. Can't do that when swapping from single to dual point distributors due to the 'offset' of the clips relative to the rotor position.
Even if one is not using that method, but actually looking at the plug wire stand and rotor position to get it 'right', it could then cause some confusion if you happened to notice that the wires were not on the 'same' stands they were originally, but rather appeared offset by one position relative to the cap clips, which could cause some second guessing. This was just an explanation of why it turns out that way.