Back in 2019 Rory McIlroy's consistency was fuelled by a new-found interest in the Ancient Greek philosophy of Stoicism.
The conclusion of his 2021 might be better defined by the Ancient Greek's notions of the dog days of summer - the stifling hot period that prompted fatigue and lethargy.
This year has delivered few golfing gifts to the 32-year-old, who's managed just three top five finishes, only one of them a win, in 19 starts.
Add in a lot of hard work on the swing, a lot of travel, and it's not surprising he's feeling it.
"I'm tired," he admitted ahead of the BMW Championship. "The game feels pretty good, but the energy levels … digging deep at this point
"Last week was long and even just summoning up the effort to get out of bed and get to your 7.20 Pro-Am tee time, it took a little more effort today than it usually does.
"It's hard to feel fresh at this time in the season. It all just catches up with you. I don't know if I could pinpoint one particular thing. It's just sort of everything blended together.
"I feel like a lot of guys feel the same right now, a little jaded, a little tired. I know I'm just going day by day and just trying to get through it as best I can. Try to make it to next week. After that, two weeks off before the Ryder Cup."
The weariness has already had one impact: he won't be flying to London for next month's BMW PGA Championship.
"Two weeks off after the TOUR Championship is going to be nice," he said. "I was planning to go over to Wentworth, but it's just too much travel, with the Ryder Cup afterwards. That's another long week."
Not all the burnout prompts are bad, however. As his daughter Poppy nears her first birthday McIlroy reflected on becoming a dad.
"Life has changed a lot," he said. "I want to spend a lot more time at home. I wanted to get home even in-between these two events.
"I flew from New York Monday night so I could get a night in my own bed Monday, spend a few hours with Poppy and Erica yesterday. Any chance I get to get home, especially at this point in the season when we've been away so much, I'm going to take it.
"I have to manage my time a little better and be a little more efficient with what I do. It's a big adjustment for anyone, but it's been great. It's the most fulfilling thing I think you'll ever do in your life, and nothing can replace that feeling."
Let's take a closer look at his form and what else he had to say ahead of the first round.
There's no getting away from the fact that 2021 has not been much fun for the 32-year-old.
The three top fives in 19 starts came at the Abu Dhabi Championship and the Olympics (both tied third), plus that sole victory in the Wells Fargo Championship.
He's got himself into contention seven times in those 19 appearances (within four blows of the lead with 18 holes to play) and four times he didn't break 72 on the final day (on another occasion he carded a 71).
Last week at The Northern Trust he produced his sixth worst performance of 2021 in Strokes Gained Off the Tee and his worst (comfortably his worst) in SG Approach.
Add in the fatigue and he looks worth opposing.
On this week's venue
"First look today. It's a big ballpark, can certainly let it rip out here, hit a lot of drivers. Been a lot of rain, so it's pretty soft, the ball is not really going anywhere, which is good. Makes the course play nice and long, which I like.
"It's a good track, good test. I have a few friends that are members here, they've told me all about it and rave about the place. I can see what they're talking about. It's a cool venue.
On playing a new course
"There's pros and cons. Sometimes when you get to a new course you don't have the memories of hitting it in places that you shouldn't. But then you go to some courses that you like and you play well on and you've got great memories, like Quail Hollow, great example this year for me.
"For the most part, I seem to do well on golf courses I haven't seen before and especially at a golf course like this. It's big, it's right in front of you. There's tons of definition. There's not many blind shots."
So the flip side of the form and tired vibes, he seems to like the course. Is that enough to take a chance and back him?
On Tony Finau winning last week
"He's such a good guy. I've known Tony for over 20 years. He's a wonderful person and he comes from a great family. Obviously, he hadn't won in a while, but he never complained. He just stuck his head down, went about his business. It was a really popular win in the locker room."