Something seems to have been lost in translation when Airbus delivered the planes to the US. I've spoken to a few of my friends at different airlines, and nobody's ever heard of waiting for gear down to select F3. I restricted my survey to fleets of 100 planes or more, and it seems we have at least 1,500 planes moving gear and flaps simultaneously.
Now just because everyone does it doesn't make it right, but it doesn't seem like a death sentence either.