[Ortho]

The books are, of course, aware of this, and so the line on the hedgeable side will often be inflated. In your example, (I'm making this up) the correct 2d half line might be Miami -3 but the books will hang 3.5 because of all the people wanting to lock up the big middle.

The answer imo is obvious: only bet the other side at halftime if that bet is +EV. Otherwise, you're just letting the book buy back a fraction of your profit in juice so you can feel better during the 2d half.