I think having a good balance or numbers and driver feedback is important but at the same time the driver feedback is a double edged sword. For example lets say I was developing a bicycle riding simulator and I came you you guys for professional bike riding feedback. Without the real world feedback and forces you might lose you balance and fall over. This never happens to you because you are a pro so your feedback would probably something along the lines of "low speed balance is too difficult". So the physics would be adjusted even if the numbers were accurate in the first place. In doing this some rider skill is added into the physics equation making the handling more approachable but perhaps not as close to reality so a careful balance needs to be made. In the end this probably is necessary on some level using the drivers feedback to know what to adjust in order to make up for all the real world forces we don't get in a sim. I think something like this was mentioned in a S3 dev stream a while back.