This question isn't about clubs or golf balls, but I'm curious how rating and slope are actually determined. I ask because my town's course, the one I play on 90% of the time, is widely referred to as being a very difficult course, but I don't think the slope reflects its difficulty. Most of the members agree that a handicap from there is at least 3 strokes higher than elsewhere. The thing is that if you look at the scorecard, it doesn't look that hard (6400 yards from the back tees). However, the issue is that every single fairway is lined with OB, hazard, or brush way too thick to find a ball. Basically, if you're not close to the fairway on every shot, it's a 2 stroke penalty. Oh yeah, every green is surrounded on at least 3 sides with badness. I've known more than a few people to loose 10-12 balls in a single round, and these are decent golfers (usually shoot in the low 80s).

Standard play is to stay in the fairway, and you can score. Get just outside the fairway or miss a green by a few yards, and take a penalty stroke. There is not a lot of scrambling resulting in a lot of doubles.

So, my question is whether rating/slope is calculated purely based on numbers, or do they take anything specific about the course into account. Personally I find it interesting that I can almost always score better on other courses even when they have a higher slope rating.