@baliktad...true that a TSO can direct a person for additional screening even without any audible alarms indicating the person needs additional screening

However, if a person has the 3 beeps - which is generally believed to indicate approval for precheck, do you really think a TSO will "get away" with not allowing that person into precheck?

The purpose of not knowing your status was to make precheck authorization unpredictable - this is meant to discourage prechecker (allegedly we the American People can trust precheckers) from bringing items that are not allowed.

Knowing your status before you even pack your luggage, allows a prechecker to do exactly what TSA was trying to discourage by way of not letting the prechecker know till the airport.

So yes, not a garuntee even with authorization, likelyhood a TSO will deny you access to precheck - when the TSO, you, and everyone else in precheck knows you are approved for it - very very small.