It is not standard procedure for all airlines. This morning, at least four non-US airlines have changed their policies.
Germanwings crash prompts airlines to introduce cockpit 'rule of two' | World news | The Guardian
Thanks. This is good to know. The "expert" gave the kind of answer that had the air of phony assurance most of these people adopt whenever they have a mic in their face. Personally, I didn't even trust US airlines to have this one covered. The taking guy did press him to reiterate that it was NOT just a US rule and he did. Another reason not to listen to someone presented as an expert.