By using S and N in the editor (small/normal) chords can be made more readable in crowded measures. Remember, each N or S applies to all subsequent chords in the chart. When you use S to make a couple of adjacent chords fit better, please use N on the next chord to reset the rest of the chart.
Because many users have small-screen devices, it's always best to use the small chord-font only when neccessary for readability.