Anyone notice the "finger flap" by Anakin and Luke?

I'm talking about after Vader pushes Luke down in the beginning of the ESB duel. Luke points his saber at Vader with one hand, and as he slowly gets up, he starts to clutch his saber with only his thumb and index, then flaps the rest of his fingers onto the saber. He also does this after he waits for Vader to aproach him in the window room.

Now, for Anakin...

During the Anakin/Dooku duel in ROTS, when they lock sabers, "I sense great fear in you, Skywalker. You have hate, you have anger. But you don't use them." They rotate when Dooku says this, and when he finishes the sentence and Anakin faces the camera, you can see him flapping his left hand before he pushes Dooku away.

So, to conclude this pointless observation, was it just a coincidence, is it genetic, did Hayden do it on purpose, or is the Graflex lightsaber too damn irritating on their hands? Please dont lock.

 

I always saw this as getting a better grip in preparation, like a batter does in baseball when choking up on the bat. Could be wrong of course.

 

Well like we were discussing in another thread about how everyone has their own style when handling lightsabers; this style appears to be more of a trait that is passed down through the Skywalker Family.