It is one of hockey’s great acts of courage: putting yourself between the puck and your own net to block a shot.

There are few comparable moments in sports, really.

It has its own myths, foremost among them Toronto Maple Leafs legend Bobby Baun scoring the winning goal in overtime of Game 6 of the 1964 Stanley Cup Final on a broken leg suffered after blocking a shot from Gordie Howe earlier in the game. It has its foremost practitioners — the Calgary Flames’ Kris Russell set an NHL record a year ago by blocking 283 shots in 79 games and somehow lived to tell about it.

He leads the NHL again this season.

And there are examples of it being an effective team tactic: Last season, the Chicago Blackhawks blocked an average of 21 shots a game on their way to the Stanley Cup, compared to the 17 shots a game they took on during the regular season, which was already the second-highest total in the league.

But the downsides are obvious. Pucks are fired like missiles these days, coming off sticks tuned like golf clubs to produce maximum velocity, gripped by men who train to be as strong as Thor. Advances to protective equipment have been considerable but injuries are almost inevitable. Get in front of enough pucks and odds are one of them is really going to hurt.

The latest example came on Sunday and, for the Montreal Canadiens, it will sting for a while. Brendan Gallagher got caught on the right hand as he came out to contest a rocket from the point off the stick of the New York Islander Johnny Boychuk.

“He was playing his best hockey, obviously,” said Canadiens coach Michel Therrien. “It’s a big loss.”

The question is — in an era when even average goalies stop 91 per cent of the shots they do face — what value does a play like Gallagher’s actually have?

As you watch the video of Gallagher’s injury, you hear Sportnet’s Garry Galley offering the understood wisdom as the Canadiens forward heads off the ice and up the tunnel to have his hand examined. He was scheduled for surgery on Monday and is out indefinitely.

“You gotta go down and block, he knows it, it’s something you just gotta do,” says Galley, who doubtless got in front of his fair share of pucks in his 1,149 games manning an NHL blue-line.

It’s a truism that is rarely challenged, and one of those things that filters down to minor hockey where kids with nothing on the line but pride mimic their NHL heroes and drop in front of shots, getting cheers for the effort.

But in watching the replay, it’s fair to ask why it’s something Gallagher felt compelled to do.

After taking the shot off his hand Gallagher spins around in pain, and ends up facing his goalie, Carey Price. And what he sees — or would see if his eyes weren’t scrunched up in agony — is the best netminder in the world, square to the point, with a perfect view of the puck. Had Gallagher given into his instincts of self-preservation and gotten out of the way, the most certain outcome would have been Price taking the puck on the chest and swallowing up the rebound.

According to Chris Boyle of the Shot Quality Project, a goalie of Price’s ilk saves an unobstructed point shot about 99 per cent of the time. In other words the Canadiens lost one of their most meaningful players on a statistically benign play. Which begs the question:

What value do blocked shots actually provide?

Which is different than asking the value of having players willing to block shots. It’s a dangerous game and having more players on your roster prepared to take a hit to be first to a puck or fight their way to the front of the net to have a chance at tucking in rebounds likely translates into team success.

Blocking shots is a highly visible example of an overall ethic that likely correlates strongly with winning hockey, that’s hard to argue.

But it wasn’t long ago that having players willing to fight on your roster was an important element of building a winning culture. As recently as a couple of years ago, former Leafs coach Randy Carlyle explained to me that when someone like Colton Orr was willing to trade punches with John Scott, it was a handy example to use when demanding other players to make physical sacrifices in different ways. But we’ve seen that way of thinking proven wrong as teams across the league have embraced the value of having quality skaters throughout the bottom of their lineups.

Does actually blocking any given shot (outside of goal mouth scrambles and the like) really help the cause of winning? And is it worth the risk of injury to presumably hard-to-replace talent?

There doesn’t seem to be a lot of readily accessible data on the matter, and the broad strokes paint a wonderfully conflicting picture.

According to War-on-ice.com, the top 10 teams in shot-blocking this season are averaging 321 blocks through the quarter-pole of the regular season, while the bottom 10 teams are averaging about 242 blocks. But the impact is negligible, at least on the surface, as the top-10 shot blocking teams are averaging 22.3 points on the season and the bottom 10 are averaging — wait for it — 22.5 points.

Again, this is an admittedly overly simple way to look at things. One presumes that weaker teams have the puck less and give up more shots, so have more shots to block while the reverse would be true for better teams.

But what is also true is there is a firm belief that blocking shots — particularly when forwards are doing it on point shots, as in the Gallagher example — is a key to winning hockey.

“If you don’t block shots, you can’t win,” one NHL head coach told me. “You can’t hook and hold in front of the net, so you have to limit rebounds somehow.”

There may be something to it, but any coach would also argue that you can’t win without talent, and in the case of the Canadiens, their cause just got a little more difficult because one of their most talented players thought it best to take one for the team.

I’m sure if Gallagher had time to ask, Price would have said “no worries, I’ve got this one.”