IdaSHO
IDACAMPER
it can be hard to explain without an animation or visual aid.
Looking at the 4-point model, pretend that the mid mounts are stationary.
Then TWIST the chassis. left front goes down, and right rear goes down.
As that happens, the front and rear pivot pivots and allows the chassis to flex, while keeping the bed flat.
Best video i can find right now to illustrate
https://www.flickr.com/photos/iandraz/3517167547/
Hope that helps.
Looking at the 4-point model, pretend that the mid mounts are stationary.
Then TWIST the chassis. left front goes down, and right rear goes down.
As that happens, the front and rear pivot pivots and allows the chassis to flex, while keeping the bed flat.
Best video i can find right now to illustrate
https://www.flickr.com/photos/iandraz/3517167547/
Hope that helps.