OK, I had to chime in...
In these situations, there will be those who are unpleasant and borderline abusive. There is a right way and a wrong way to deal with it. The wrong way is to lose your temper and argue with them. If a TSA agent takes his frustrations out on you, such as described - making snide comments, reminding you they are in power - DON'T SAY ANYTHING OTHER THAN WHAT IS REQUIRED - AND SMILE. Don't argue, don't overexplain, just smile and say "it's my scuba tank - I emptied it and removed the valve for you" yadda yadda.... "These are regulators for life support" ect... if they ask.
If they confiscate something and you don't agree with it, or it is an expensive item such as an analyzer, ask NICELY to see a supervisor - ask NICELY for some paperwork. They have full authority to take something away. They DON'T have full authority to take a $500 peice of equipment and keep it forever. Come on..
When you are done with the "gauntlet" and survive, do what another poster should be commended for doing, file a complaint.
Write everything down as soon as you are clear of the "incident" while it is still fresh. Write down times, names, numbers, exact phrases used, ect.. These details add enormous weight to a complaint. Odds are that this person has been abusive to others as well. Your complaint might be the final straw and weed out someone who does more harm than good in this position.
These people have a responsibility to protect the flying public and national security. They DON'T have the authority to abuse their power, berate travelers, or yell at old ladies slower than they are. They can't take away your medication just because you can't produce a doctor's note - come on... That's what the labels are for. If you pack meds in a little plastic bag, however, I think you deserve what you get - alot of questions!
Personally, I have at least 50 trips under my belt over the last year to the East Coast. I have never been treated unprofessionally. As a matter of fact, the majority of these agents have been nice, and have even smiled.
I'm a firm believer that copping an attitude with security agents is the quickest way to a bad situation for everyone around.
Divers travel with things that look "out of place" as compared to the normal person with a bag of underwear and the like. We need to be prepared for questions. I learned this over many years as a travelling engineer. Try explaining why you have peices of a combat aircraft in your luggage! lol, I just tell them the truth, but keep it simple. "It's a hard drive for an XX aircraft - I work for XXXX, here's my badge.." "Sure, I have some more paperwork right here.."
I never have a problem and usually get questions like "How can I have a job like yours?"
The same thing works for scuba gear...
The key here is HONESTY and POLITENESS, and patience until you get to thier bosses!
James