Since your association has made it a POE, it is obviously something that needs attention in the area. It is a disservice to the crew that comes after you if it was not addressed in your game(s). Bench Decorum is a POE at most levels this year and it is quite likely that it has also been communicated to the teams in your area, so they are also aware. In essence, they have been notified and expect it to be enforced. I would also suggest that before you start "whacking away" a reminder statement could go along way in dealing with a coach that got caught up in the moment.
Now with all that in mind, I think that the situation needs to be taken into consideration. Remember that if one coach is abusing the box, they are gaining an advantage over a coach who is adhering to the POE. So, I offer a couple of thoughts that I use in such situations. "Have I previously communicated to the coach about their conduct? Was their comment directed at the officiating crew? Are they overly animated? Is the coach distracting us from officiating the game?" And this last one, "If I T this coach right now, will it improve the game?"
Several years ago, when I was getting started, I found some information about T's. It is a pretty good reference. I found it on another website. Many people here are already familiar with it. Go to:
http://www.chsaa.org/officials/baske...p10Reasons.pdf