[Chris is me]

This isn't a "secret trick" - this is what every competitive team does. There's nothing "secret" about an extremely loud buzzer sound.

Really, the "secret trick" is that the 0 second mark appears before the buzzer sounds. You should have your hands on the controls before the robot is teleop enabled. The drive coach should be staring at that clock, counting down the last five seconds, with some audible cue the moment a zero appears.

The reason there was a delay to enabling this year, was because extra time was added between autonomous and teleop to allow balls to fall through the goal sensors. You will notice this delay in shooting games more than games scored through other methods.