Things I hate

[Freddy]

Rather than having to say something after the fact, how 'bout if you include "which OB lines we each cover" in your pregame--the visual aid of a court diagram will all the more seal the concept.
And while you're at it, be sure to cover which partner signals the three point attempt where outside the arc. That way the "having two guys signalling a three attempt" will more readily be avoided.