CCW'ers ,do you keep a round in the chamber when you carry?

when my cousin was in firearms training in Arizona the feds wanted all tribal officers to pull there weapons acquire a sight picture, then bring it up on the target, my cousin disagreed with the instructor, just like he disagreed to carry a full magazine and no round chambered, his thought was keep a round in the chamber, and safety on, takes less then a tenth of a second to flick off the safety and bring it straight out like you were throwing a punch, those that had to "lock and load" from the magazine always were last in qualifying times! so yes on keeping a round chambered, safety on