Haha, don't worry. It hasn't been fully figured out yet. Basically, there's several radii coming from the origin of the prop as I understand it. One defines the magnitude, or height, of where the "trunk" ends and the leaves begin, in all directions. This part stays stiffest. There's an even outermost radius that determines where the leaves end. You see these defined near the start. Might be hard to tell because everything's so small, and that's because I basically wanted my prop NOT to have a trunk, so it all swayed.
As it seems, vertical sway is made to be much less frequent as it would be for a tree (this is so trees don't bob up and down). It's almost entirely horizontal. But the different values in the screenshot above can tweak these, ex the "scrumble" values (have no idea what that word means!).
Beyond that, the other values are pretty self explanatory. You have strength, which is how much it sways, and speed, which is how fast. Both of these can usually be tweaked to give you want you need alone. But it's recommend you include all of the above parameters. It's quick to test everything too by using "reloadallmaterials" in console, refreshing the VMT.
It takes a lot of experimenting so I recommend testing it on a random prop. For mine, I sampled everything from one of the new palm tree props included in the jungle update. It even came with those helpful comments next to each value
