Boat weight and speed ?

[Boardfox]

The other day I went out in my Buddy's X2 and we loaded it down with about 3000lbs and used a rope length of 80'. To get the wake shape perfect we had to ride at 24mph. My question is once you get to the point where the boat is loaded down so much that you have to increase your speed to make the wake clean how much good does adding extra weight do you? My intuition says that the wake would not get any bigger when adding extra weight at this point because the extra weight will make the wake wash out which means you have to ride faster to get a clean wake. So once you reach this point, to keep a clean wake adding extra weight just increases ridding speed and the wake size will stay the same. Am I correct on this theory. All you engineers out there help me out.