The wiki says prop_statics cannot move or animate yet we all know the prop "props_island\island_tree01.mdl" from mercenary park that has a wind-like animation. How did valve do that? What's the limitations? I tried decompiling the model but I couldn't find anything useful... it's in the material island_tree_trunk01.vmt, apparently they added the $treesway feature in jungle inferno..
The animation is a vertex shader, not a typical bone based mdl animation. I think the shader is applied through the material.