This has been debated here at length, and I DO mean length.
The outcome? We agreed that it is not a good practice, exposes shooter to possible cataclysmic failure of gun, and should not be attempted unless you find yourself under attack by King Kong and have nothing but birdshot.
We also felt it encouraged novice shooters to try something really bad so we closed the discussion, and closing this one for same reason.
What we have here is... failure- to communicate.