I never touched a golf club until about June of 2011, I was 21. Didn't get instruction of any kind, even my dad wasn't any good to be able to teach me anything. He did give me a 50 year old copy of Hogan's 5 lessons, which I read a few times.
Now I hadn't been a natural athlete either. I was good at martial arts and baseball, but never did any sports until I was 14 and didn't stick with either after about 16. Never really got pushed by my family to compete or get better, had no real competition from rivals or anything. I was 6 feet and 150 pounds, which I still am. Not physically gifted by any means, though I had well above average flexibility. I was never a power hitter in baseball, either. In the interest of full disclosure, I have 2 blood relatives that I know of who are PGA teaching professionals, but I've only met them once or twice. So maybe golf runs in the family a bit, but it certainly skipped plenty of the men in my family.
When I first started playing, I hit occasional drives about 200 carry and 220 total when I hit them well, used about a 9 iron from 110 and a hybrid for anything over 150. Certainly my mechanics weren't good since I flipped at the ball and had a wicked slice. I've improved my swing to the point I can hit drives around 300 or more if I try to, my 9 iron is now 155 and my 5 iron is about 205. The slice is gone and I'm hitting penetrating shots that stop quickly. I've done most of my improvement in the last month or two, in which I've hit about 1,800 balls with my full swing since 4/21 when I got a range membership. Probably only about 30 hours of really good, immersive, regular and consistent practice without weeks in between sessions like the first 2 years I occasionally played. I'm now hitting a controlled draw, with lots of height, center contact, lots of compression and speed and the divot after the ball. (Turns out range mats don't mark your clubs unless you hit them before the ball. Even hitting 50 shots with one club, hitting down aggressively won't do much. Range balls will also stop on a real green most of the time if you strike them well, and you can almost always tell if one will fly straight or if it's damaged. All stuff I learned from this practice.)
As it happens, my grouping with a 5 iron is a lot better looking than his as well. I've been taking the opposite approach to his plan, practicing mostly full swing and only spending between half and 10% of my practice time around the greens as I've been trying to iron out my swing lately. I think the improvements to my full swing have carried over to the short game, however, especially the plane and release. Just haven't been able to play much at all, so it's tough to quantify progress.
I've been practicing for closer to 400 hours since I started playing than 4,000. Yet I can still outdrive Dan by about 50 yards after falling out of bed without being what I consider an elite athlete or over 6 feet. Hitting up is part of it, but I can still carry my 3 iron off the ground farther than most of his drives and certainly my hybrid beats even his longest. There's also the fact that the fairway is 50 yards or wider and he can barely keep his drives in, which he needs to do to get by in competition with so little distance... His mechanics are lousy, plain and simple. He only hits his 5 iron 170, about the average for the LPGA. Then there's the fact he only hits his 5 iron to a height of 55 feet. That alone makes it nearly impossible to play good golf on a long course, especially with tournament greens. Maybe he can putt, that is certainly nice, but it keeps him out of the 90s rather than getting him under 70.
I'd have to ask the following of Dan:
-Can he hit 5 balls showing a divot after the ball?
-Can he present the proper dynamic loft to the ball to hit an effective shot?
-Can he control his trajectory?
-Does his ball stop on the green?
-How many out of the 5 keys does he have?
-Does he think he can get to scratch, let alone a touring pro without these abilities?
All those abilities are totally technique, not like having a 30 inch vertical. You can do all of them on a 10 yard pitch shot if you want to. Even a guy with one leg can do most of them pretty decently. The girls on the LPGA can do all of them, old men with good swings can do all of them, a 14 year old kid can do them if they're exceptionally well taught. Not everyone who can hit the ball well is a great golfer, though.
So I am able to surpass his ballstriking ability (and therefore scoring potential) by a fair bit within a tenth of the amount of practice. I don't consider myself especially talented, and I don't outscore him. I could probably do decently against him in match play though. I'm certainly not great, but being able to learn that much faster with no instruction must mean either talent does exist and therefore he sucks, or that I'm a better instructor than his, which means his instructor or his plan really sucks. I think he shouldn't necessarily give up, but he needs to change his swing if he wants to consistently play well. I buy into the existence of talent, if only as a mentality, and I certainly buy into the 65/25/10 ratio for practice as a general starting point.