I think limiting the placement of high PB value players on the farm has some merit in theory, however at the specific player level its a little tough to implement.

Say I have Bonds, and know he's going to have to sit for at least 15 games or else he'll be worn out before the end of the season. I might want to sit him against certain teams (poor teams I should beat without him, teams not in my division) so I know he'll be ready when I need him the most. Since I don't want the robot using him at all, I might choose to send him to the minors for a few away series. I don't want to have to wait to send him to the minors until he is overused.

I think maybe something could be worked out in regard to total PB value, so that a team had to have at least 65% of its total PB value active at all times, but limiting the movement of specific players might not work.

Fred