The metrics that define that line?
In men's golf, there are five golfers who competed during the four-major era (mid-1930s on) who stand above all others. "We think it's a great way to champion what the PGA of America golf professional does and the relationship with the tour". Ben Hogan. Gary Player.
"Collectively, these moves should be a good thing for the game of golf, and I am supportive of anything that benefits our game and at any level", Nicklaus said.
Jordan Spieth already has shown a remarkable sense of the moment.
"Do I have to be the youngest? It's very hard, but if you hit good shots you can make some birdies".
It is rarified air, and the world will be watching.
"I think the changes are really good there", McIlroy said.
But they have been an integral part of the PGA Championship since its start in 1916, and perhaps even more so since the tour players broke away in 1969 to form what is now the PGA Tour.
Patrick Rodgers plays from a fairway bunker on the seventh hole during a practice round for the 2017 PGA Championship at Quail Hollow Club on August 9, 2017.
McIlroy, 28, who owns four majors, has made three attempts to finish off his slam at Augusta National. But he hasn't cracked the top-10 otherwise, sharing 21st at the US Open, 37th at the British Open and 39th last week in Akron. "I have let my insecurities get the best of me at times".
Thomas Pieters is one I like again in a major. Just seven years later, in 2009, it held another U.S. Open and has since host the PGA Tour's Barclays in 2011 and 2016.
He would seal victory with a messy par five on the 72nd hole to prevail from Mickelson by a shot.
"In weighing the complex evolution of the golf calendar, the PGA of America's key objectives were to promote the best interests of our signature spectator Championship, do what is best for the game and its great players, and find the most advantageous platform to fulfill our mission of serving our almost 29,000 PGA professionals and growing the game", said PGA of America chief executive officer Pete Bevacqua. "Each major provides such a different set of challenges". Beyond that, the switch to May could allow some venues that weren't capable of hosting the tournament in August to now be in the mix - particularly in states such as Texas, which hasn't hosted a major since 1969, or Florida, whose last major was the PGA Championship in 1987. He has not won anywhere since. That will change when it goes to Bethpage Black in May 2019, falling between the Masters and the U.S. Open.
Neither did Spieth. He missed a playoff by one shot. (He'd finish second in four U.S. Opens). I believe this year he turns it into a 1st at The PGA Championship.
Less than three weeks after he won the Open Championship, Spieth's only real concern was the Charlotte humidity. He was six months shy of 25.
He won his first major title at the 1959 British Open and his last at the 1978 Masters.
The best putter on tour for much of his short career until this year, the Texan was a picture of frustration on the firm and super-fast newly re-grassed greens, often walking after his ball as soon as it had left the putter-face. Ernie Els, in what might be his last PGA Championship, shot 80 for only the second time in this major.
"I can absolutely understand some of the logic, and if it ends up as resulting in more people watching our game, then that's a great outcome".
"It was really just on the greens", Spieth said of his problems. "So it's kind of a nice thank-you to them".
I still feel like the golf course gives you plenty of chances.