Other than the fact the neutral zone trap (a defensive strategy) caught on and eventually spread throughout the League and the increase in clutching and grabbing, what exactly changed after the 1994 Lockout in terms of defensive play?
It wasn't as if all these new super amazing defensemen showed up suddenly.
Goaltending equipment obviously grew in size during the 90s (maybe too much).
Yeah, it's a good question. As memory serves, overall scoring dropped quite a bit from 1985-86 to 1986-87, then went up a bit again from 1987-1989, and then from 1989-90 there's a fairly noticeable drop in scoring up to 1997-98 (the exception being the shortened Work-Stoppage season, which was unusually low, probably to do a lot of back-to-back games vs. division rivals only).
So, it's a continuum, not a sudden drop off... 1995-96 was pretty high scoring, still. It's really during 1996-97 when the scoring levels really start to taper off. Nevertheless, there had been a general downturn since 1986-87.
(Cue
Canadiens1958 with a post about the "short shift game"!)
I suppose there are a lot of factors there, including the obvious things like (yeah) the short-shifts increasing (decreases chances of scoring due to fatigue, or scrubs vs. stars), goaltender athleticism increasing, the 'butterfly' style increasing, size of goaltenders increasing, size of goaltenders' equipment increasing, etc., etc. I also think the increase in the size of the NHL (expansion) created a lot more parity, and more parity means less skilled players assembled on any handful of particular teams, which in turn means less chance of dominant teams being able to "out-skill" other teams to victory. Consequently, teams instead tried defence-first.
But one thing that I think doesn't get mentioned enough in this transition is Youth vs. Age. From the late 70s through, maybe, the late 80s, good teams and even dynasties (Edmonton) were built around young players. If you go back and look at NHL-team rosters c. 1981 to 1985, you find a lot of teams with a lot of really young players. I mean, Tom Barrasso came into the NHL straight out of high school, was a #1 goalie (for Bowman, no less), and won the Vezina. That's inconceivable today. Pretty much every team drafted 18-year-olds and threw them into the line-up right away. And 18 or 20-year-olds don't play defence as well (or as much) as older players do. By contrast, those 18-year-olds in 1982 were 32-year-olds in 1996 and were still going strong as 1st-liners, and were still among the game's biggest stars and biggest scorers. Simply put, there were a lot of older 'stars' in the 90s than in most previous and subsequent eras. That also has the tendency to keep scoring down.
