After my initial post on the impact of curved blades, I forged ahead looking at game footage of what I refer to as the "heightened game" (meaning, the game after curved blades). Yet there was one thing that was interesting to me, particularly in regards to shooting. Yes, there were more "drag-and-snap" snap shots being taken in the 1980s, and yes curved blades were prevalent, ditto saucer passes (among the better teams), ditto off-the-glass dump-ins. But there was one thing that didn't seem to come around in the 1980s, and it involves where mama keeps the cookies.
I really began to notice it after a goal on Richard Brodeur in 1981 where the announcer said that he was beaten "top shelf." Really, he was beaten about chest height on the glove side, but as I continued to watch I realized that direct, unblocked shots were still very low, even in instances where the goalie clearly was focused on covering down low (check out this Gretzky compilation, for instance). In reality, focusing everything down low had been the norm in goaltending stances for quite some time, a fact that continued into the 1980s. Observe Richard Brodeur here, Tom Barrasso here, Mike Liut here, John Vanbiesbrouck here, Mike Palmateer here, and so on. The catch glove is low, and the pads are frequently nearly upright and exposing only a minor V. That was the primary goaltender stance for a majority of NHL history, from Bill Durnan to Jacques Plante to Ken Dryden (not my intent to list Canadiens goaltenders), and it made sense: they were putting their efforts towards the area where majority of the play and shots were coming from. The stance also artificially brought the head down and forward, which was more dangerous but also helpful in seeing through traffic.
Of course, we know that isn't the whole story; Glenn Hall and Tony Esposito broke the mold with their approach to the goaltending stance. Both were equally concerned with coverage, namely the low areas of the net, but had impressive leg speed and sought to use it to their advantage. They each developed their own style of spreading their legs out yet bringing the knees down at the same time, creating wide coverage down low. In Hall's case, he still had the old stance (see here), but as the action got close he was quickly prepared to drop to this splayed position. With Esposito, he kept his five-hole wide open, practically taunting shooters before closing the door. Esposito's initial stance fell into an easy version of Hall's butterfly. The success of these approaches was undeniable (Hall and Esposito were considered two of the best at their position despite frequently playing on middling teams), but the impact on the game was even greater:
1. The Role of the Glove Hand
Look at those older pictures, especially in regards to the catch glove. It was a leathery, shape-shifting beast from the 1980s on back, better for covering and slapping people in the shower than catching a puck...far removed from the deep-pocketed puck trap we see today. This was appropriate to its role; it covered, it blocked, and could catch if need be, but really it functioned as an agile complement to the side of the often cumbersome (and, as the game went along) heavy leg pads. Now notice the glove in the butterfly pictures of Hall and Esposito - it operates above the pad. In the modern era, this has helped free the glove to focus on the middle and upper areas of the net, creating a greater opportunity for highlight-reel saves (and bringing a realization that it would be helpful if the gloves had deeper pockets to snare the shot). I remember as a kid toiling with late-1970s to mid-1980s catch gloves in youth hockey, always frustrated in my quest to deepen the pocket on those damn things.
The butterfly pulled the goaltender's head back from the leaned-forward stance of their forebears and widened their base, and any sacrifice in vision was compensated for by promoting a steady sitting position (if the stance is correct, the gloves will be forward from the bent knees). The goalie crouch we know now was greatly influenced by the butterfly, and it helped increase the goaltender's ability to cover low and high.
3. Top Shelf
As I mentioned above, the game in the early 1980s still was played fairly low, though it became more commonplace to see individual shooters try to shoot a bit higher to beat the goaltenders (particularly those with greater curves on their stick, like Paul Coffey). This probably explains why you still had the low stance with success throughout the 1980s and into the 1990s (Barrasso and Beezer would largely continue their stance), though textbook stances would evolve to move the legs apart a bit more and bring the gloves up to adjust for the higher game. Even so, there was a market inefficiency there, and soon curve enthusiasts started adding more "flick" to the blades (there's even a web forum for these folks), and top shelf became a thing almost alongside the flourishing of butterfly goaltending. I'll leave it up to the readership to speculate if one or the other had a causal effect, but I'd argue that the butterfly stance helped goaltenders make the adjustment from altering the old, low and/or stand-up stances (as "textbook" goaltenders did in the 1990s) to adopting a stance that was more stable, reactive, and consequently better for recovery against the heightened game that emerged from the 1980s. On the flip side, the butterfly's strength down low has bolstered the desire for higher shots, and the desire was met by further stick innovations. Top shelf today is, literally, as high as you can get (think Wheeler's goal last night).
The butterfly's pervasiveness is nearly absolute today; it's almost part-and-parcel of the textbook approach now, and many of those who aren't considered "butterfly" are called "hybrids" because they still contain some of those butterfly elements. The sustained success of the stance, and the emphasis on getting padding that complements and maximizes the butterfly's effectiveness (Patrick Roy's true contribution to goaltender evolution), have brought us to a place where we'd never been before: the near-pinnacle of goaltending capability.
P.S. Those interested in reading a bit more on this should take a look at "Mike @ MHH's" comments below. Thanks Mike!