Swammy, as the TSA will gladly tell you, any TSA inspector, at any location, has a pretty much unlimited discretion to forbid you to carry on anything they say, even if the official TSA policy allows it. If the carrier discourages it, or the airport
discourages it, of the TSA guy just isn't sure what it is, it goes in the trash.
I had a sealed package of a very nice goat cheese confiscated before "it could be plastic explosive, we don't know". I've been told the same thing about long zip-ties "because you might be planning to restrain someone with them". Although, shortly after 9/11, I did accidentally carry two, not just one but two, nail clippers on board, and those were expressly banned at that time. Really, like I'm going to give someone the Death of A Thousand Snips with them?
Anything that can be used as a "cudgel" (hockey stick, camera
tripod, cannibal bone in your hair) "may" be banned, at the discretion of an inspector. Same thing for any restraint. Last time I flew, the regulations
had changed to allow EMPTY butane lighters to be carried, previously all lighters of ay kind had been banned. So while I'm watching the nice lady try to figure out if my boots were deadly weapons, two inspectors were conferring over an empty butane lighter in the next lane, trying to decide if it could be allowed onboard.
Oh, my boots? According to long-standing pubished TSA guidelines, all "orthotic" devices must be allowed to remain ON the passenger and to proceed ON the plane. But you'll never see orthotic boots allowed until they've gone through the x-ray machine.
Sure, you can appeal the inspector and ask to see the supervisor. TSA policy is that a supervisor will never, ever, embarrass the TSA by overriding an inspector. Unless it is something totally beyond the pale, whatever the minimum wage guy says, stands.
I've had a guy at SeaTac goes nuts when he wanded me with a metal detector and it went off. What was it? Oh, I missed A PENNY in the lining of my pocket. But if you put the same penny under your watch? No one ever questions it.
Don't try to use logic here, it is all about FUD and putting on the dog and pony show to re-assure the rubes that they are being protected. Protected by the same airline industry, and the same Congress, that collaborated to shut down the US air marshal system in the 1980's, contrary to global standards, and allow 9/11 to happen here.
Duct tape? It might be allowed, might not. I used to see guys on Air Alaska
carrying SawZalls, and small chain saws, complete in their metal carry cases, and no one questioned letting them into the cabin. Somehow, they
never tried to cut an airplane apart, either.