At this point, it doesn't matter because everybody stinks. Change purely for the sake of change.
The #3 spot is a place of privilege and Zimmerman has lost the privilege.
LaRussa did something one year when the Cards had hitting problems. It goes speed/avg/power then repeats and would look like this(?) Morgan-Gonzo-Dunn-Guzy-Johnson-Hammer-Zim-Bard-pitcher. He did it just to shake up the line-up.