Wade geared with springs?

Here is an image from reprap wiki-

could someone explain the use of springs on this version of Wade ?
I’ve heard a few times that it is good to have some sort of give/spring in the system


Thats basically just a different type of idler arm assembly with 4 bolts instead of 2 bolts and a pivot point. You can’t see the idler bearing there. the springs compress the idler bearing against the hobbed bolt, pinching the filliament. Some people like that style because it puts more even pressure on the flilliament at the meet point. I personally like the standard 2 bolt style much better. It’s less finicky.