Its a nice Arod Batting practice bat. Their is no photographic evidence of Arod using a Blonde Lvs in a game, but quite a few pictures of him using them in BP and warmups. The same goes for blonde and black Rawlings bats.
Here is ARod with a blonde bat on Aug 24, 2003. He used blonde LS a few times in games in 2003 which was certainly not the norm as you are right that it was his Black LS that he used almost all the time.
Here's a couple of pics of Arod and Giambi heading into the batting cages at Fenway. Arod is holding a blonde LVS. The last photo shows Arod using a blonde Old Hickory during the 2004 season.
