Forget everything you’ve ever heard about continuity and chemistry fostering good offensive line play.

The Giants have.

The strategy of indiscriminately rotating three tackles and soon-to-be three guards through the left side, right side and the bench completely bucks conventional norms, but the Giants’ offensive line issues have been so pronounced for so many years involving so many different players and coaches that maybe “Opposites Day” was the only stone left unturned. So, why is it effective?

“We’ve talked a lot about that internally, to be honest,” coach Joe Judge said. “Part of the reason may be it gives our guys a little bit of a breather and they’ve got fresher legs out there. Part of it may be it changes what the defense can do to attack you — they can’t single up on what one guy does and maybe it alters how they approach each drive not knowing who is going in.”

Mark Schlereth — who played offensive line for 12 years in the NFL and has been an NFL on Fox booth analyst for two Giants games — has another idea.

“Sometimes it’s good to light a fire because you don’t get to play all the time, so you better understand what you are supposed to do,” Schlereth told The Post. “I think there’s been more attention to detail for young players.”

Schlereth and a teammate alternated by the quarter during the 1994 season. No merit-based exceptions.

“It was the dumbest thing in the history of football,” Schlereth said. “Normally I would criticize the rotational aspect, but a lot of it is, ‘Let’s figure out what we’ve got.’ When you are in the process of building a football team, you need depth. This is not just about this year. It’s also about building for the future.”

The Giants didn’t revolutionize football — the same five linemen playing together over the long term, studying each other’s tendencies and sharing one brain remains the preferred blueprint — but they have at least temporarily stabilized a weakness with a Pop Warner-like “everybody plays” strategy.

“The one thing we’ve concluded is whatever the reasons on the other side may be, we like how it’s working for us,” Judge said, “and we’re going to keep on going with it.”

The offensive line paved the way for a season-high 166 rushing yards and ranked a season-best 11th in the league in pass-blocking efficiency against Washington, according to Pro Football Focus.

Three of rookie left tackle Andrew Thomas’ four highest single-game grades from PFF have come since he, right tackle Cam Fleming and rookie swing tackle Matt Peart began rotating. Thomas played 68 snaps, Fleming 64 and Peart 24 against Washington.

“All three guys are playing well right now for us,” Judge said. “They’re all improving, so it gives us a lot of confidence to keep moving those guys on through.”

The Giants are about to adopt the strategy at guard, too. Rookie Shane Lemieux held his own during Will Hernandez’s two-game absence on the COVID-19/reserve list and will continue to get snaps when Hernandez returns to starting opposite Kevin Zeitler.

“For the Giants, what you saw was a lot of technique mistakes early — whether it was footwork, sets or not understanding where your help is,” Schlereth said. “There was a lack of awareness because you’ve got a bunch of young players. There’s a process where you say, ‘We’re struggling, we’re going to get everybody some reps, and we’re going to see if the cream rises to the top.’ ”

Schlereth also saw the Giants simplify the demands between Weeks 4 and 6.

“At that position, you have to find something to hang your hat on and then build from there,” Schlereth said. “When you have a lot of volume up front, there are going to be a lot of mistakes.”

The loss of spring workouts and preseason games due to COVID-19 turned the first quarter of the season into the Giants’ learning period.

“Continuity is a big piece, but we also have a unique situation,” Zeitler said. “We have a lot of young, very talented linemen in the room. Given how the season has started, I think the ability to get them in there has been really good for us.”