I remember one of the few times I played 4E D&D, I was a Con'lock specialising in pushing, and a few other character also had a lot of ranged push abilities. We ended up pushing the big bad so far away (14+ squares) it couldn't attack, then the avenger managed to convert the pushed squares into damage (I forget the power/item/thing used).
Is there a maximum range allowed on push per turn? Should there be? What we did seems excessive.