Does it count as "extraordinary circumstances" that I carry a Leatherman pretty much everywhere I go? Since we became scared of everything sharper than a thumb, I've had to check a bag if I want to travel with my multitool, which I don't think is terribly unreasonable.

I used to routinely fly with it on my person. I'd take it out of its sheath, put it in the basket for keys and change and such at the metal detector, and hand that to the uniformed agent standing there. I was never once challenged for this, or even looked askance at.