Tanks, Rebreather Bottles and Spare Airs May be Confiscated

[DanL]

The forbidden item is listed as "compressed gas cylinders". Perhaps the basis of the different interpretations is that an empty, open tank is not a "compressed" gas cylinder, but an "empty" gas cylinder.
Here's an added twist: I just asked the TSA inspector at the Philadelphia airport (I was on a business trip) about traveling with a small gas cylinder. He said it could not be cleared because even if the reg is removed and the inside is visible, there is no way to tell if something dangerous was within the walls of the tank, since x-ray can't see thru the walls!
My guess is this isn't going to be cleared up any time soon.
Question - why doesn't DAN or Rodale's or, oh my gosh! even PADI, act on behalf of rec scuba divers and address this formally with TSA? Could probably be easily resolved with just a few communications.