The inconsistency is a major aggravation for me as well. I can carry something for a dozen flights, then it will be flagged. Once a bag search is done, there is a strong tendency to find something -- anything -- that justifies their search.

It doesn't matter if the rules say that the item is allowed. Carrying a copy of the rules won't help. What is allowed is entirely at the whim of the TSA agent. Sure, you can disagree, but you will always lose -- they can make you miss your flight. And if you insist too strongly, they threaten you with arrest.

Some of the suggestions such as mailing items or putting them in checked bags might work for someone doing casual/vacation flying, but you shouldn't extend your limited needs of easily replaced items to everyone. Sometimes the things you travel with are vital to the purpose of the trip.

For a professional photographer, there isn't any point in the trip if your camera and lenses aren't there for you to use. Checking in $40K of equipment is completely out of the question. Getting a replacement at your destination is often impossible.

I've traveled with unique, one-off items needed for demos and trade shows. But me and the equipment have to be there for the trip to be worthwhile. If the equipment isn't there for a trade show, the opportunity is lost forever.