That is about as comprehensive of an explanation you are going to get. I am a little concerned over the trend, just the past couple of years, to recommend shafts that are clearly over spined for a particular bow. And some of the discussion on here that there is "no such thing as an over spined arrow shaft". Certainly, having too stiff of an arrow is going to give you less problems than too soft of an arrow - but ideal is where you want to try to be.