PGA Tour pros rarely go into new tournment course without having played there before. If that is the case they have atleast 3 practice rounds to come up with an idea and knowledge about the course. I really think some courses you need more than that but these are tour players. They also have help of their caddy that maps the greens and figuring yardages as they practice. They aren't going into this like a pop quiz in high school... they had a few days to study. I think it depends on how tricked up the course is. It probably not a good idea to play a Dye course without some help....that can only be a nightmare. I think having someone that has played there before is a major help. I agree going in completely blind you can expect some errant shots not knowing how the course is setup. I don't think its that high maybe 4-7 depending on skill level.