I teach that if a team puts down a special hand, scoring is done as the condition exists. Meaning, if the opponents get stuck with 3 aces or sevens they have a 2500 point penalty. If the opponents have made a couple of canastas they get their points for them and for their 3’s. you are inquiring about a ”newer” table rule called ”knockout”. If a team puts down a special hand it will knock out the opponents canastas and 3’s. That is a table rule I don’t teach or play but certainly can see how that would be very exciting!