I've been hoping for a rational rebalancing of the rules -- even if it meant a pouch that went on the "excess carry on" cart that most domestic flights now have, and which is inaccessible to passengers during the flight.

Things that go "boom" take down aircraft; clearly, the new rules relect this. Any fool that tries to take control of an aircraft post-9/11 with a SAK will need to be vacuumed out of the carpet -- passengers will not sit quietly. And in practical terms, I'm pretty sure security will have a fair amount of discretion based on behaviour and other indicators.