Yeah, this is why I qualified it with "the closest thing I can think of ..." It wasn't his first trip around that place. But I have a rebuttal to that as well ... two of my best all-time scores (the one time I broke par many years ago) and when I shot a 76 on a 7400 yd. course in Montana a few years back were both courses I've still to this day only played once.
I don't think this is a valid argument. The "depth of field" arguments and the Tiger V. Jack arguments where its frequently pointed out that nearly all of these guys is capable of winning any given week suggest that the dropoff from top tour player to average tour player isn't very far.
Also overstated IMO. Most of us play on courses with at least decent grooming. The amount of times my ball is knocked off line by a deformity in a green is probably similar to the amount of times I've ended up in a sand filled divot.
If you want to continue, you need to find a good instructor. Your low handicap friends hopefully can give you some names of instructors that they recommend. I am usually in the 90's so I know the feeling of good shot/bad shot great putt/four putt.
I can't fix your swing, because it can be so many things, but I can tell you that what usually throws me off is when I try to tweak too many things and before I know it I am so far removed from where I came from... that is where an instructor can hopefully clear all that garbage out of your mind.
I wouldn't say I'm the same, but I have similar issues that scare me off of my 4i a lot. I have lengthened shafts because of my height, and it's pretty much a good thing. However, I don't hit my 4i well. I need to try choking up on it sometime, to see if that helps. Usually, I have a bit of a straighter stance with it. I similarly stand up and adjust my stance with my 3H, because it doesn't feel right in my normal stance, and the head is tilted noticeably at address. I guess I just decided that standing up a bit on those clubs was easier than adjusting my grip or paying to have the clubs cut.