[JeffM]

I know that slapping the backboard is neither a technical foul or a violation.

I'm not certain what to do if my partner calls it. What if I'm the R? What if I'm the U/U1/U2?

I believe I should stop the game and have a brief conversation about it with my partner and hope that I can quickly change his mind and changes his call to an inadvertent whistle. Depending on his experience relative to mind would determine how much I would encourage him to change his call. I would tell him that we would discuss it at halftime or after the game. Of course, it would not be a correctable error at that point.

Does that seem like a reasonable approach?