A key factor of course rating is based on yardage. So changing established tee yardages can be extremely detrimental to any net tournament. That’s why we explain to the courses (to the point of exhaustion) to never stray from your course scorecard yardage. Even if it’s too short/long a course for the player, which we still want to avoid, the course rating is accurate if you play from the scorecard yardage.
Once in a while we see what Harry referenced.. a bunch of players beating the course rating for the day. But we’ve established a contingency on the off chance it does, provided it was due to improper course setup and not pin placements, LCP, etc.. which are not a component of the course rating system.