Your understanding is absolutely correct. Indeed, that sign opens the lane up to a whole host of people. Inexperienced flyers (see: New to flying), Families, Special Assistance, and, of course, Medical Liquids in excess of 100 ml.
I would complain about the TSO's idiocy as well as the AA contract flunky.
Originally Posted by
FlyingUnderTheRadar
Kinda of like when I was at PDX and tried to use the elite lane and TSA said I could not when the sign said that was what it was for along with crew. They were letting crew threw but no one else.
Complain to the airline and the TSA. The airlines very clearly control everything up to the TDC.