I will say this - In civ III it gave you the ability to transfer population quickly from one city to another, giving the target city a boost in productivity. Of course, it imbalanced the food/population ratio so each turn (or few turns), your population boost died off.
This really isn't much different than the related topic of sending migrants to other countries and affecting their culture and gaining benefit from it yourself. The only difference is here you're just doing it within your own borders.
As for whether or not I support this idea, I suppose the jury's still out.