I don't know if I would be able. It's usually not a problem to hit the empty net from center ice 90% of the time but considering that the event takes place during an intermission, probably before the zamboni, and in front of a crowded arena.. and not on skates. I would think the trick is to have your feet facing the net so that you don't have to rotate your shoulders when you shoot.
It's way harder than it seems... I know it since I made the ''méchant Millions'' contest. I had 14 in on 20 wich is not bad but in practice it was always 16+.
1. You are very nervous
2. You have 20 second to shoot 20 pucks, you don't realy have the time to look if you first shoot was in the middle of the net or not.
3. The pucks are kept warm so they are sticking to the ice.
4. You don't have you skates on.