Re: Techies will continue to sneer.
"*stares at kits of TSA master keys for sale*"
From experience, luggage does get checked by the TSA. (We had a suitcase delayed by half a day because we changed planes and our suitcase got looked at by them, and didn't make it to our flight.)
Ultimately, it all boils down as to whether you can check a suspicious case without opening it, and if not, *how* do you allow access to the various agencies whilst providing security to passengers.
For the record, I know my cases have been rifled through in other countries, and the TSA is the only agency that have left a polite note saying they had done it. (No idea what they were looking for.)
I've never lost anything from hold luggage, but then I'd never intentionally put something valuable in there....