bpurple I would forecast the game to continue on as it does today. The current clogging of the game didn't come about because the coaches decided "Oh, wow what are we going to do with all these reserves of energy from interchanges? I know, I'll use them to swarm around the contest!" The interchanges became a way of making the extra numbers around the ball more effective, because getting more players where the ball is is a strategy that works really well. In the scenario of minimal or zero interchanges, if one team decides to save their energy it is likely to become like a game of chicken as one team sends more players to the contest at the start of a game when they're fresh, because of the superior numbers they start to win more contests slam on more goals, what do you think the other coach is going to do? Wait and hope as the other team draws away? Then as the game draws on, the team with the lead would start to find ways to slow the game down, no matter how ugly it gets, so they can hang on.