There’s a fantastic book called “Grit” by Angela Duckworth that deeply examines what goes into high achievement. Grit is also a hockey term often associated with third- and fourth-liners, and their willingness to do the hard duties required over the course of a hockey game, like win board battles and block shots.

But Duckworth is talking about greatness, the kind of greatness we often just write off to talent that we mortals wouldn’t ever be able to understand -- think Connor McDavid flying through the neutral zone or Alex Ovechkin’s perfectly placed one-timer.

Duckworth argues that great achievement isn’t some unreachable stratosphere but instead a fairly simple formula: Talent multiplied by effort equals skill. And skill multiplied by effort equals achievement. Effort, Duckworth points out, counts twice. It’s twice as important as talent or skill.

Grit, in the non-hockey sense, is the daily effort and resilience required to ultimately produce great achievements. It’s constant, it can be learned and it’s inspired by a lifelong passion.

Sidney Crosby has been described a lot of ways as he’s re-established himself as the best player in the world over the last year, but according to this definition, he might be the grittiest player in the NHL. And it was Taylor Hall who really made the connection, even if he’d never read this book. I mean, maybe he read the book. I didn’t ask.

“I say this in the best possible way possible, Sid is the best grinder in the league. The most skilled grinder,” Hall said. “He works so hard and creates plays out of nothing.”

Shea Weber put it this way: “He’s the kind of guy that continually works on his game. He works as hard as anyone, getting better and making sure he maintains his abilities. He’s going to be good for a long time.”

That grinding mentality that Crosby possesses, one that makes him obsessed with improving his game incrementally on a daily basis, is part of the reason he’s now approaching 1,000 career points at the age of 29.

It’s also why it was a bit flawed that we would expect the next phase of generational talent -- led by McDavid and Auston Matthews -- to immediately enter the league and surpass him.<!--offer-->

Watching McDavid last season, you saw a talent unlike anyone who had entered the league. You saw a will to work and improve that came in the form of video proof from YouTube training videos that went back years.

This season, watching Matthews, it’s a different kind of player but equally impressive. There’s strength on the puck that a teenager shouldn’t possess and a confidence to make plays that allowed him to hit the ice sprinting in his NHL debut.

It’s all there. What they didn’t have was time. Crosby has had a decade of incremental improvement to go with that same rare skill. If effort is in the achievement equation twice, he has a gap that can’t be closed on his younger generational counterparts.

So instead of seeing these young players immediately join the league and pass the older stars, Crosby has reminded us all just how good he is and how hard he will be to pass. In the process, he has his fellow players wondering when, if at all, McDavid and Matthews will pass him.

“As long as Sid is playing, I don’t see anyone passing him,” said Stars forward Tyler Seguin. “I think Connor is a great player but they’re different. Connor’s speed, quickness, agility -- his first few strides are incredible. Sid still has that fire, that competitiveness, that big ass you can’t get the puck off of. As long as Sid is playing, I don’t know if anyone is passing him.”

At some point they will. It’s inevitable. As good as Crosby is, he’s also human. In a time where the prime age of forwards is getting younger and younger, that he’s leading the league in goals at 29 years old is pretty remarkable.

There’s an inevitable decline that’s going to hit in the 30s that even the grittiest superstar can’t avoid.

So the conclusion Blue Jackets forward Cam Atkinson makes is probably closer to the right answer.

“It’s one of those things that is definitely not going to happen in a year,” Atkinson said. “[McDavid] is showing signs he could be the best player in the world. You look at a guy like Crosby, who does it on a nightly basis and he’s been doing it for 10-plus whatever years. That’s why he’s the best player in the world. That’s what the best players do ... they do it on a nightly basis.”

When weighing who he thought was the best player in the game, Wayne Gretzky said it’s a mantle that has to be earned over time. One great season doesn’t do it. Two probably doesn’t either. That’s why Crosby is firmly in that spot, according to Gretzky.

Plus, part of it is accomplishments. To earn the title there has to be some form of team success and for McDavid and Matthews, that’s going to take time.

Crosby is sitting on two Stanley Cups and two Olympic gold medals. McDavid and Matthews might not even get a chance to play in the Olympics, a stage where reputations are made.

Think of Crosby’s most memorable goal; it came on the ice in Vancouver in overtime against the Americans in 2010. To be considered the best in the game, there have to be similar moments, moments McDavid and Matthews haven’t even had a chance to make yet.

“What Sid has done with Stanley Cups and gold medals, the accolades and awards he’s done, you have to think they have to match that or be better than that to take over the title as best in the world,” said Columbus defenseman Zach Werenski. “Skill-wise and playing ability, they’re close. With what Sid’s done in the sport, with winning, how young he was when he lifted the Cup, winning the gold medal -- you have to match that or be better to be titled the best.”

That, too, takes years.

The consensus from players is that McDavid has a smaller gap to join the conversation with Crosby as the best in the game, although Matthews has certainly entered that debate.

“He’s an elite scorer and a guy who can find open space fairly easily in the offensive zone,” Hall said of Matthews. “I don’t know how he compares to both those guys. I think they’re at a different level but the way Matthews is producing his rookie year, you can’t deny that he’s an amazing player.”

Amazing, in Hall’s eyes, but not quite at the same level as McDavid.

“With Connor, you can see the play coming from a million miles away but you can’t stop it,” Hall said. “Just like it was Crosby vs. Ovechkin for so long, it’ll be Crosby vs. McDavid pretty soon.”

Just maybe not as soon as we initially thought.