Well, a better way would be to screen everyone entering the sterlie area. Without any exceptions of prejudice. Any "trustred traveler" group only serves to create loopholes that can be exploited.

A lot many countries manage to keep their strelie areas truly streile by enforcing blanket screening of everyone that seeks to enter them. Be it a fellow screener, a flight attendant or a Member of Parliament. And they manage to do it without the Kabuki Theatre of checking ID's, removing shoes and confiscating harmless containers capable of carrying more than 100ml of liquid.