All meaningless. The final ok is from the person behind the desk. That's all. That person at that time is the law. Doesn't matter what the real law, or policy, or regulations or rules are. It's all up to the guy behind the desk. It's like traveling to any foreign country. The law sits right behind the desk. He or she has the final say. At the TSA check they are god. What they say is final. Doesn't matter what the airlines say, or what FAA says. It is up to TSA that will allow or not. Nothing else matters. You can show links, letters, testimonials, and all is worth zero, nada, zilch. You can have terminals taped over, you can have discharged batteries, you can have the battery uninstalled, etc. What TSA decides at that time is all that counts. You can of course ask for a supervisor, but if the supervisor agrees with the search agent, that's it and it's final and it's tough shyte. All you can hope for is you get the right agent at the TSA search area when you're going through. (assuming you are following all the rules talked to about in this video)