Technical question
 

Center makes his final adjustment of the ball, the rest of the line is set with hands on their knees. The line shifts into a three point stance and the center, without removing his hand from the ball and in a very deliberate manner, also shuffles his feet as the line shifts. This movement in no way resembles the start of a play. Everyone is set for a second before the snap.

Is the center’s movement a legal shift?

Yes, it's a legal shift.