This video is a comparison between the most used up/down movement, made famous by Richard William in his book "The Animators Survival Kit" and the movement I observed in the references.
At Left == My Observation's result At Right == Method by Richard William
The one at the Right has a nice appeal but it's not very natural, I'd be happy to read your opinions about both of the ways.
Rig by Gary Wee and Jimmy Wijaya
