Yes, as long as he does it in a smooth non-play-starting motion...
and anyone else that shifts does so in the same manner, then are set for a full second after they are done "shifting"
Rule reference would be 7.1.2
ARTICLE 2.
a. Shift. After a huddle (Rule 2-14-1) or shift (Rule 2-22-1) and before the snap, all Team A players must come to an absolute stop and remain stationary in their positions for at least one full second before the ball is snapped, without movement of the feet, body, head or arms (A.R. 7-1-2-I).
b. False Start. Each of the following is a false start by Team A if it occurs prior to the snap after the ball is ready for play and all players are in scrimmage formation:
1. Any movement by one or more players that simulates the start of a play.
2. The snapper moving to another position.
3. A restricted lineman (Rule 2-27-4) moving his hand(s) or making any quick movement. [Exception: It is not a false start if a Team A lineman immediately reacts when threatened by a Team B player in the neutral zone (Rule 7-1-5-a-2) (A.R. 7-1-3-V)].
4. An offensive player making any quick, jerky movement before the snap, including but not limited to:
(a) A lineman moving his foot, shoulder, arm, body or head in a quick, jerky motion in any direction.
(b) The snapper shifting or moving the ball, moving his thumb or fingers, flexing his elbows, jerking his head, or dipping his shoulders or buttocks.
(c) The quarterback making any quick, jerky movement that simulates the beginning of a play.
(d) A back simulating receiving the ball by making any quick, jerky movement that simulates the beginning of a play.
5. The offensive team never coming to a one-second stop prior to the snap after the ball is ready for play (A.R. 7-1-2-IV).