So rob, how do you explain the fact that if you weigh the axles with WD hitch attached and without WD hitch attached, the weights will change by several hundred pounds?
Oh wait I know why; because the downward force on the scale changes. Which is the meaning of weight as used in this context. Hence a weight distribution hitch does work; it changes where and/or how the downward forces are applied.
Same with sway control, it changes how and/or where the forces are applied. While your description may be technically correct (although your assumptions about cracking the frame aren't), the laws of "simple" physic still apply. Applying outside forces changes the vectors.
