LEMONT, Ill. -- In the four weeks that have passed since one of the biggest rules snafus in major championship history, the debate over whether that patch of sand at Whistling Straits constituted a bunker has raged among all levels of golf followers.
Dustin Johnson and his caddie, Bobby Brown, have heard it, oh, say a million times, often with some wise guy in the gallery bellowing out "it's not a bunker" as the golfer sets up to play a shot.
The mistake Johnson made at the PGA Championship -- regardless of your take on the bunker fiasco -- is the type of thing that could scar a player for life.
Only a handful of players are frequent contenders at golf's biggest tournaments, and to deny yourself a shot at victory because you grounded your club in a hazard it still defies belief.
Johnson had to live with that, on top of his Pebble Beach implosion, where he took a 3-shot lead into the final round of the U.S. Open, triple-bogeyed the second hole and went on to shoot 82.
He had a chance two weeks ago at the Barclays, playing in the final group with Matt Kuchar, and shot 72 to tie for ninth.
So, yeah, Sunday's birdie-par finish at Cog Hill and a final-round 69 to win the BMW Championship by a stroke over Paul Casey was bigger than one of Johnson's mammoth tee shots.
"Everybody around here knows exactly what we're dealing with since that Sunday at Pebble, and this one is special, you know what I mean?" Brown said. "I'm not saying he's going to be the best player in the world, we've got a long way to go for stuff like that. But I don't think I'd switch bags with anybody."
Johnson put it more simply.
"To finally get it done, especially after all the things I've gone through this summer to finally get it done on Sunday, it can't feel any better."
The long-hitting player from South Carolina actually has gotten it done on several occasions. This was his fourth PGA Tour victory, but easily the biggest of his career.
He earned $1.35 million and moved to second in the FedEx Cup standings, which means the 26-year-old Johnson -- along with Kuchar, Charley Hoffman, Steve Stricker and Casey -- controls his own destiny at East Lake.
If any of those five players wins the tournament, he would capture the FedEx Cup and its $10 million bonus.
"That would look nice in the bank account," Johnson said, smiling.
As big as all these paydays are -- Johnson is now second on the PGA Tour money list to Kuchar with more than $4.3 million this year -- what the victory signifies is probably worth more.
The questions about Pebble Beach and Whistling Straits are not likely to subside -- with comparisons to Roberto De Vicenzo surely to be part of golf lore -- but at least the sharpness to them will have dulled with such a nice, satisfying victory to follow.
"Pebble taught me a lot," he said. "That's where I learned the most I think after getting off to such a rough start. I kind of maybe got a little fast. Everything starts moving fast in a situation like that. So I really learned to be patient and not rush things.
"I didn't rush any shot today. I took my time, took practice swings. Even when I felt myself trying to rush a little bit, I would stop, put my club back in the bag and come back and go through my routine and just take things slow."
A bit of help from Casey didn't hurt, either. Ranked ninth in the world, the Englishman was looking for his bit of redemption, too. Having been spurned by European Ryder Cup team captain Colin Montgomerie two weeks ago for one of the at-large picks, Casey was in a great position to post a satisfying "take that" victory.
After birdies at the 11th and 12th holes, Casey had a 3-shot lead. But then he made three straight bogeys to fall back into a tie with Johnson, whose 54-degree wedge shot to a few feet at the 17th hole set up the birdie that got it done.
"Congratulations to Dustin Johnson," Casey said. "He's gone through a lot the last month or so and he obviously played wonderful golf."
If it was big for Johnson, it was huge for Brown, too.
In the aftermath of Whistling Straits, his caddie acumen was called into question because he, too, failed to recognize that the 18th-hole bunker was just that, leading to a 2-stroke penalty that knocked Johnson out of a playoff with eventual winner Martin Kaymer (who won again Sunday in Amsterdam) and Bubba Watson.
"I'll be the first one to tell you that I think we were in a wash-out area left of that bunker on 18 at Whistling Straits," Brown said. "They probably should have put him in a golf cart and taken him back up there to look at the situation instead of going by TV.
"Hell, yeah, I read some stuff that wasn't cool. That wasn't cool at all. But the only thing that matters to me is that big dude right there. And he was fine with it. We had a brief discussion about it.
"I've walked by bunkers for so many years and so has he. We're firm believers in things happen for a reason. And good things happen to good people. And he's one of them right there."
Now it's on to the Tour Championship, where Johnson hopes to add those zeroes to his bank account, and then to Wales, where he is already proving to be a popular potential partner for his U.S. Ryder Cup teammates.
And the focus now changes. Instead of doubts about closing, there is the good vibe that comes from winning.
"You know," Johnson said, "it makes things a lot easier."
Bob Harig covers golf for ESPN.com. He can be reached at BobHarig@gmail.com.