Yup, the 20 minute card worked really well in Super Rugby.

For anyone that doesn’t know how it worked…

1. Something happens that warrants a card.
2. On field referee gives a Yellow* and sends for review, player goes to the sin bin.
3. After review by the TMO, if warranted the card would get upgraded to Red; the captain gets notified - it could take up to 8 minutes to complete this step.
4. The team would remain at -1 players until 20 minutes from the start of the original card.
5. After 20 minutes the carded player can be replaced, returning the team to full strength.**

*It never happened that I can recall, but for something that would be a straight red like punching / kicking / biting the referee could still give that, it didn’t have to always be Yellow. **The player carded does not come back on, and automatically goes to the judiciary for further review & additional sanction.

What was great was the game kept going, no 5 minute break while the on field referee ran closer to a big screen and tried to figure out what had happened from a 1080p image blown up to 5m wide. It also took the crowd out of the decision as the TMO worked through it with access to all camera footage and a specialist TV assistant (for the video & camera angle stuff, not the laws).

Other than the actual sanction this is what the bunker does as well; and its a great innovation. I just wish the sanction had been adopted too, but the opposition that I heard was mostly that up north there was a belief that cynicism would see teams accept 20 minutes with 14 players if it meant they could injure an opposition player out of the game, which is just absurd but is how some folks look at the game I guess.