That's in part, Sanderson says, because the legendary Bruins defenseman rewrote the game in the 1960s into the 1970s, revolutionizing the position, playing in a way that had never been seen before, or since.
And it's sadly, he says, because so much footage of Orr has been lost forever, a Boston TV network's film library of countless Bruins games tossed into the garbage during a move.
"All that we get to see is a few reruns of Bobby doing the same thing," Sanderson said. "We never get to see Bobby at his best."
It's almost unfathomable that there is more impressive footage of Orr than what has been assembled in the NHL Network Originals documentary "The 1970 Boston Bruins: Big, Bad & Bobby," which premieres Sunday (8 p.m. ET; NHLN, SNE, SNO, SNW, SNP).
Video: The 1970 Bruins: Big Bad & Bobby trailer
There is grainy film, in black and white and color, of No. 4 rushing up ice, braking, reversing direction and pulling back into his own zone, killing a penalty.
There are breathtaking sequences of Orr at full speed and in slow motion, slicing through the opposition with ridiculous ease, undressing checkers, pirouetting, spinning, diving, passing through lanes that don't seem to exist.
There is film of Orr crashing to the ice, injured, and being interviewed in his pajamas as he recovers.
And of course, there is Orr on May 10, 1970 pitchforked into full, glorious flight, having just scored 40 seconds into overtime of Game 4 of the Stanley Cup Final against the St. Louis Blues, a goal and a photo for the ages.
Orr may be the centerpiece of the new documentary, but the production is much more than a highlight reel of a single player. It is an hour-long celebration of a city's enduring love affair with its blue-collar heroes, through plenty of thin leading to the delicious thick.
The 1970 Stanley Cup-winning Boston Bruins.
Narrated by Ken Casey of the Boston band Dropkick Murphys, the documentary features the insight of a host of Massachusetts natives. They include actor Denis Leary; 13-season NFL defensive end Howie Long; Mike Eruzione of the 1980 gold medal-winning U.S. Olympic hockey team; and author Thomas J. Whalen, whose new book "Kooks And Degenerates On Ice" profiles the 1970 Bruins.
Three influential writers, who for decades have chronicled the Bruins, offer their observations: Kevin Paul Dupont of the Boston Globe, ESPN columnist Jackie MacMullan, and New York-based hockey historian and NHL.com contributor Stan Fischler.
Sitting together to remember the championship team and the years that came before it are Orr, centers Phil Esposito and Sanderson and goalie Gerry Cheevers. Separately, contributions come from Bruins cornerstone Johnny Bucyk, forward Ken Hodge and Bruins mastermind Harry Sinden, who coached Orr for the first four of the latter's 10 seasons in Boston, including the 1970 Stanley Cup.
"It's about a team that played a half-century ago, long before this city became the new Titletown, U.S.A.," narrator Casey begins, visuals reminding of the NFL's New England Patriots and baseball's Boston Red Sox.
The Bruins, Casey crows, "were old-school. They were misfits and marauders, wreakin' havoc on the ice and becomin' gods wherever they went in town."
And that's not the half of it.
Harry Sinden in 1970 and appearing in the Bruins documentary.
"They galvanized the whole state," Eruzione says of the skilled, muscular team that would become known as the Big, Bad Bruins. "How do you want to play? You want to play with skill? We'll out-skill you. You want to fight 'em? They'll outfight you. You were going to either get out-talented or you were going to get beat up."
For too long, Sinden suggests, the Bruins had lacked an identity. It didn't help that from 1959-60 through 1966-67, they finished outside of the Stanley Cup Playoffs in the six-team NHL.
Fans still filled Boston Garden, but with almost gallows humor, expecting embarrassment on home ice.
The weathered Garden, Dupont says, "was a dump, but it felt like a palace. … There was a charm to [the Bruins], even though they lost."
Legendary Bruins defenseman Bobby Orr and goalie Gerry Cheevers in action.
The 1966 arrival of the highly touted Orr, from the Ontario Hockey League's junior Oshawa Generals, was the spark the franchise needed. The native of Parry Sound, Ontario was viewed as the savior, a lot of weight to drop on an 18-year-old's shoulders.
The youngster brought "a new sense of hope," Sinden says.
As Orr gathered steam and thrilled fans, Bruins general manager Milt Schmidt was about to electrify them with a trade. On May 15, 1967, Schmidt acquired Esposito, Hodge and forward Fred Stanfield from the Chicago Black Hawks for forward Pit Martin, defenseman Gilles Marotte and minor-league goalie Jack Norris. It was a blockbuster, and ultimately a heist in broad daylight.
The Bruins would be swept by the Montreal Canadiens in the first round of the 1968 playoffs but returning to the postseason was a huge victory.
Derek Sanderson and Bobby Orr as they appear in the documentary.
Esposito says he remembers pulling Sinden aside after their elimination and telling his coach, "We're going to win the Cup in three years."
Esposito, who would become the greatest sniper of his day, went long by a year, Boston bounced by the Canadiens in a six-game second round in 1969 but bound the next season for a championship the Bruins hadn't won since 1941.
There was swagger to spare by now, a hard-earned edge that was in the team's every pore.
"We were cocky, we were arrogant," Hodge says with a grin. "And we backed it up."
Bruins cornerstone Johnny Bucyk today and in 1970.
Arriving full-time in 1967-68 was the flashy Sanderson, a playboy who squeezed every drop out of life, then found one drop more. He had the city at his feet, and he was the embodiment of the Bruins' new attitude.
"I sat beside him the whole time and he entertained me, I could tell you that," Esposito says with a laugh.
Bruins faithful jammed the Garden, camping outdoors in a makeshift cardboard and plywood village during the playoffs to get their hands on the hottest ticket in town. Their beefed-up heroes were no longer the League's doormat but mopping the ice with opponents.
Orr's magical Cup-winning goal 50 years ago this Sunday -- Mother's Day in 1970, as it is again a half-century to the day -- is a thing of mythical proportions in Boston and well beyond.
Goalie Gerry Cheevers and center Phil Esposito as they appear in the documentary.
"I don't know what bar or restaurant in Massachusetts doesn't have that picture," Eruzione says of the flying Orr.
Esposito ties the bow for those who lived this glory and for those learning now about the 1970 championship, arguably the greatest moment in franchise history.
"For me," he says, "it was the perfect time, perfect place, the perfect team."