Relating my own experiences as a golfer, the game is indeed more mental than anything. Granted, I'm a 10-handicap playing on cheap public courses, but a lot of the same stuff still applies. The physical portion of the game can use tweaks from time to time, but it's largely muscle memory.
Put simply, if you're able to truly clear your mind and have confidence that you can land your 7-iron within 15 feet of the pin, you'll succeed more often than not. Have confidence that you've judged the ensuing putt correctly and it has a pretty good chance of going in...that's how you score birdies and pars instead of bogies.