Dabo Swinney is not hesitant about much.

On the load of players skipping bowl games, Clemson's coach believes that "everybody kind of lives their life in fear. Anybody can get hurt in any game. Why play your senior year at all?"

On quarterback freshman Trevor Lawrence bringing home a Heisman Trophy in the future, Swinney thinks, "we already should have had one. [DeShaun Watson]. … If the good Lord keeps him healthy, he'll have as good a shot as anybody."

On the College Football Playoff, Swinney bucks the trend. "I'm not a fan of it. … I wish we went back and had two teams. That was some of the greatest experiences that I had in my life. Experiences going to the Fiesta Bowl, Independence Bowl, Blockbuster Bowl and spending a week somewhere and playing some random team."

But ask Clemson's coach about one of the foundations of his program, and he hedges. What, he was asked recently, will be the legacy of Clemson's celebrated defensive line?

Christian Wilkins, Clelin Ferrell, Dexter Lawrence and Austin Bryant have played together for three years. They've made a combined 625 tackles, 75 of them sacks.  

Clemson promotes the quartet as the only returning four All-Americans on the defensive line in college football history.

Back to that legacy question. Swinney hesitated.

"That's to be determined right now," he said. "They're in the process of living that legacy right now. That's what they came to Clemson to do. I told them, 'Don't worry about leaving one, live it.'"

That's Dabo. That's Clemson football. Never satisfied. This is a program that watched a former starting quarterback transfer (Kelly Bryant) only to get better at the position.

"Obviously, he's got peace in that decision," Swinney said of Bryant, now at Missouri.

Meanwhile, we are watching history on that defensive line. Think of Notre Dame's Four Horsemen or Chuck Bednarik playing all 60 minutes for Penn or Oklahoma State's Barry Sanders setting the rushing record so far out of sight you need a telescope.

We may never see the likes of No. 2 Clemson's defensive line ever again.

"They wanted to be the best ever," Swinney said. "That's been a clear vision for them coming into this season. They've articulated that to me every single day."

No. 3 Notre Dame knows it has to go directly through that line in the Cotton Bowl semifinal to get to the CFP National Championship. 

"You probably have three guys there that could be top 50, top 60 players in all of college football," Notre Dame coach Brian Kelly said.

Yeah, but which three? Ferrell (6-foot-4, 265 pounds) is a long edge rusher with 26 career sacks. Dexter Lawrence (6-foot-4 350 pounds) is a force with one of the most desired traits in defensive football: He collapses offensive lines on his own. Wilkins (6-foot-4, 315 pounds) is a run stopper so athletic that he played safety in the spring game. Bryant (6-foot-6, 280 pounds) wasn't messing around in a spring game last season; he split out to cover a receiver.

All four are draft-eligible.

"Even if we get beat in the Cotton Bowl, these guys have had an amazing journey," Swinney said. "I've never had a defensive line like this across the board. I've had great individual leaders, but collectively as a group, it's off the charts. These are great men. There's just this chemistry to them."

Editor's note: Lawrence is expected to be suspended from the Cotton Bowl after a postseason drug test administered by the NCAA flagged the presence of ostarine in his system. 

How amazing? Clemson has won four straight ACC titles and is in the College Football Playoff for the fourth straight season. From the beginning of the season, it has always looked like an Alabama-Clemson rematch in the CFP was inevitable. The teams have met in three previous years in the postseason. Clemson won once, claiming their second-ever national championship in 2016.

How amazing? Pro Football Focus has Clemson's cumulative pass rush rated No. 1. The cumulative run defense is rated No. 2. Only Northern Illinois has more sacks than Clemson's 46. Only Miami has more tackles for loss. Now consider freshman defensive end Xavier Thomas may be the best of them all on that Clemson line despite playing less than 30 percent of the snaps, according to PFF.

"I thought, earlier in the year, they were a little overrated," said Steve Palazzo, PFF senior analyst. "Only because everybody thought they had three top-10 picks. Dexter Lawrence's three-year career has been terrific. Christian Wilkins has improved as a pass rusher greatly. Clelin Ferrell improved, but again, I don't know if he's a first-rounder."

If first-round status is the standard, that's against Swinney's culture. As a group the starters have proved, they are in no rush to leave. Lawrence is the only true junior. Wilkins completed both his undergraduate and master's degrees in 3 ½ years.

"When you kind of just breeze through and hurry up and get out, you miss a lot," Wilkins said. "I feel like I slowed down, appreciated the aspects of Clemson."

Wilkins will be missed as a self-described "old head." There will be a bit of closure against Notre Dame. It was in a home game against the Irish four years ago that many say announced the Tigers as a national contender.

Clemson survived 24-22. The Tigers have gone 50-4 since that game played in a driving rainstorm.

"I remember that game like it was yesterday," Wilkins said. "Your boy got his first career sack versus Notre Dame."

Swinney has long sold "fun" at Clemson. "Winning is not our No. 1 goal," the coach once famously said.

It looks like that stance will never change. 

"He likes to pinch everybody on the butt," Swinney said of Wilkins. "If you watch him on the field goal team, he loves to slap them on the butt, pinch them on the butt. He'll walk by me and pinch me on the butt from time to time. I can't do anything about it."

Swinney got his pinching revenge when Wilkins raised the Campbell Trophy, often referred to as the "Academic Heisman," earlier this month in New York.

"I don't know what he's talking about," Wilkins said, smiling. "There is no story there."

Wilkins took it upon himself to take Trevor Lawrence to breakfast during the season. That was during what Swinney called the "quarterback drama" -- Lawrence taking over and Bryant leaving.

"It was obviously an interesting situation and a lot going on," Wilkins said. "It was, 'Let me just see where this guy's head at a little bit.'"

The head, the arm, the Tigers are all fine. Lawrence and Thomas are freshman All-Americans. But if that veteran defensive line is the best ever, doesn't it need to go out with another national championship?

Wilkins didn't hesitate.

"Consistency is hard to accomplish with 18-to-22 year old kids," he said. "We've got good quality people to carry on and continue the legacy."