A possible solution may be to have a /focus (mage name) macro for your dps. Whenever he pulls aggro you can switch their focus to him, hit your follow macro, which would make them start following him. If they're close enough that they don't have to move toward him, they'll simply turn and face him and therefore the mob.

I haven't used it for that purpose, but I have some formation macros, and something I noticed is that I can hit follow and they face my focus, which can make for some different formations.