I’m aware this absolutely not the same thing but in league of legends eSports, at international tournaments the teams in the tournament often practise against each other in the lead up to and during the tournament.

Pretty notoriously, the teams that do the best in these practise matches essentially never win. Grand final matchups where one team has 100% record against the other in “scrims” only to get completely demolished in the final.

My point is, practise is wasted if you don’t lose it to try things that might result in losing.