One hundred and fifty-six players teed it up on Thursday and Friday at the US Open, but you only needed to watch two of them - in the same pairing, no less - to see the different way Congressional's Blue Course can be played.
The right way, at least if the scoreboard is anything to go by (and, more often than not, it really is), was demonstrated by Rory McIlroy. The 22-year-old played as near to flawless golf as you are ever likely to see in a major championship, hitting 20 of 28 fairways from the tee over the opening two days, and a deeply impressive 32 of 36 greens in regulation.
He made birdies, lots of them, and even an eagle - from the middle of the fairway on the 8th, where his wedge shot spun perfectly back down the slope and into the cup. A double-bogey at the last may have left a slightly bitter taste in the mouth, but prior to that he became the first person in the 116-year history of the event to make it to 13-under par - and his 36 hole total of 131 shots is nevertheless the best US Open record books have ever recorded.
McIlroy was dominant, of that everyone can agree. His display brought to mind the sort of dominanting displays golf has only seen from Tiger Woods in recent seasons - at Augusta National in 1997, and Pebble Beach in 2000.
McIlroy was obviously delighted with his own ball-striking, yet afterwards couldn't help but marvel at his playing partner - whose navigation of the course could hardly have been more different.
Phil Mickelson has managed to hit just 13 of 28 fairways this week (despite deferring to his two-iron more often than not) and has managed just 21 greens in regulations. He has been forced to hit over trees, under trees and even sometimes through trees - and still been left with numerous chip shots that would outfox the mere mortal.
Despite all that, the American is just one-over par for the tournament - and that after emulating McIlroy in making a water-assisted double-bogey down the last.
McIlroy may be leading, and by some margin, but even he was in awe.
"He made some really good up-and downs today," McIlroy noted about Mickelson. "He had a disappointing finish, as well, at the last, but he was under par for the tournament going into the final hole.
"From an outsider looking in, I don't know if I could have been under par for the tournament hitting it in some of the places that he did. But he's just got a phenomenal short game and a great attitude. He just forgets about some of the bad shots and just goes and almost relishes the challenge of getting it up and down. He's very impressive around the greens."
It's difficult to argue that Mickelson has played better than McIlroy over the two days, but there's something in it. Many players could have reached lofty numbers were they hitting from every fairway and putting from the middle of every green - but basically no-one could have stayed within touching distance of par were they forced to extricate themselves from the sort of places Mickelson was finding with abandon.
Rory McIlroy praised Phil Mickelson's scrambling
The American is a four-time major champion, though - so he doesn't exactly find much cheer in pulling off escapes the other 155 in the field can only dream of, especially if it means he sits 12 shots off the leader.
"It was a disappointing finish with that double, but I'm still struggling," he commented. "Even though I was able to shoot under par today, I was still struggling with it.
"Rather than work on it, I think I'm going to try to figure out what it is I need to work on first, and then get back to the range."
He knows he must start finding fairways and greens if he is to get in contention - if that ship has not already sailed. The biggest threat to McIlroy's charge for the title, other than a similar meltdown to the one that afflicted him at Augusta just over two months ago, is his swing suddenly falling out of sync and forcing him to employ what has been an under-worked short game so far this week.
Fortunately, the 22-year-old has been wise enough to learn from the master he has been fortunate enough to play with for the opening two days. Even in the midst of his record-breaking run, the Northern Irishman was enthralled by Mickelson's Houdini act.
"I actually sort of caught myself trying to just sort of watch some of the chip shots he played today just to see if [I could learn anything]," McIlroy revealed. "Because he's sort of looking around everywhere, looking at different parts of the green, how he can bring it in, you can see all those little thoughts going through his head, it's really cool."
McIlroy's swing will desert him at some point this weekend - if he's lucky only for a few holes, if he's unlucky for the whole 36. That's just golf. No player escapes without at least a couple of bad shots. With so few of them over the opening rounds, the balance of probabilities suggests he is due a couple over the weekend. The task then will be to make like Mickelson and escape without penalty.
For now, however, McIlroy has everyone chasing his dust - and none of them can have any complaints.
"It's impressive," Mickelson said. "He's striking it flawlessly and he's putting great on these greens. His first two rounds were very impressive."
Two rounds down, two to go.
Hopefully McIlroy keeps playing so well he doesn't need to put his short game to work - but if he does, maybe playing with Mickelson has given him the added edge he needs to avoid another harming major defeat.