SR rating is just a number next to your name. If you really want racer to behave you have to give them a reason too because a higher SR. Give them more XP or Credit. There has to be a payout at the end beside just finishing first. You also need to reinforce that behavior through the Campaign mode. Example : Have mini-games or driving licensing test that teach the game how to behave on a track. Teach them how to recognize situation and what to do in that situation. You cannot do any official races until you have the "Sportsmanship" licenses or have specific events that requires the "sportsmanship" license to enter . The whole concept of clean racing has to be enforce through out. It's very hard to break 20 years of GT habits. For the longest time, it was just faster to use the AI to break or bounce through a corner because the car is almost unaffected, there is 0 damage and it just plain faster to do it that way. You cannot expect the same population who has played this game the same way for years to change overnight. It is the same problem with Forza on Xbox. I don't even dare to go online.