While we all still have to occasionally fight it out with specific airlines when flying with our instruments (until the new weight restrictions go into effect) one important thing I recently discovered was contact numbers for the TSA Customer Support Managers at individual airports.
Even though it's always a relief when the airline accepts the bass without a fuss, you still often have to worry about what will happen to the bass during TSA inspection--at least, for the airports where they do that behind closed doors. I've heard several horror stories about the TSA repacking a bass terribly, leaving latches or straps undone, and other issues that have caused damage.
If you call the national TSA number (1-866-289-9673) and select option #5, you can ask to get the name and contact number of the TSA customer support manager at your airport. I've done this before, and told the manager of my situation, and why it's very important that I watch while they inspect the flight trunk. I was very impressed when they went to extra efforts to work out the logistics to make this happen, and it has made going to the airport a much less stressful ordeal. I've done the same thing for the return flights, and so far, I've had good luck (as long as you call a few days ahead so they have time to figure things out.)
And another perk is that when the TSA manager walks up to the airline counter with you and explains to the desk agent that you've made special arrangements for inspection, they sometimes are so focused on that they forget to charge you oversize fees
Interested to hear if anyone else has had luck with this . . .
-Jeremy