Penguins making most of offensive chances

The Pittsburgh Penguins hold a 2-0 series lead against the San Jose Sharks in the Stanley Cup Final, and that's because they're getting the puck on the net. The Penguins have outshot their opponent in 11 straight games and in 16 of 20 during the Stanley Cup Playoffs.
In the regular season, Pittsburgh led the NHL with 33.2 shots per game, ahead of the Los Angeles Kings in second place with 32.0.

So far in the playoffs, the Penguins have averaged 35.1 shots per game, third behind the Florida Panthers (39.2) and Chicago Blackhawks (36.6).
There are several Penguins among the playoff leaders in shots; Phil Kessel leads the NHL with 83, Patric Hornqvist is tied with Brent Burns of the Sharks for second with 67, Kris Letang and Evgeni Malkin are tied for No. 7 with 60, and Sidney Crosby ranks ninth with 59.

Despite Pittsburgh's success, having the higher shot total doesn't always lead to victory. The Penguins are 10-6 during games in which they outshot their opponents, and 4-0 when they do not.
The 16 teams that qualified for the postseason are a combined 36-51 when they have outshot their opponent.
This is the result of a phenomenon known as score effects. Simply put, a team chasing a late lead tend to open up and put everything on net, in the hopes of creating some scoring chances with tips, deflections and rebounds.
At the same time, a team protecting a late lead tends to sit back and focus more on getting the puck in deep and killing time than on getting more shots. The impact of these playing style changes are that much more noticeable in the playoffs, when teams are more closely matched, and it's winner-take-all; there are no extra points for an overtime or shootout loss.
That's why the enhanced stats section of NHL.com includes shot-based metrics exclusively in close game situations, when score effects don't come into play. Other websites measure the impact of these score effects and use that to calculate adjusted forms of the most popular shot-based statistics.
However, these score effects do not explain the Penguins' high shot totals. In the regular season, Pittsburgh started the third period with the lead in 39 games, were trailing in 30, and tied in 13. In the playoffs, the Penguins have started the third period with the lead 11 times, trailed four times and were tied once. Consequently, score effects have been working against Pittsburgh and actually reducing its shot totals.

Unusually high shot totals sometimes can be the consequence of generous scorekeepers, but that's not happening in this case, either.
Not all goaltender saves are counted as shots. If, in the scorekeeper's judgment, the puck would have missed the net, then it is marked as a missed shot instead of a shot on goal. In some cases, the scorekeeper is more likely to give the benefit of the doubt and count more saves as shots on goal.
This phenomenon is called scorekeeper bias, but it isn't responsible for Pittsburgh's high shot totals. According to a
recent academic paper
by Michael Schuckers and Brian Macdonald, the latter now the director of analytics for the Florida Panthers, this only significantly impacts the way shots are recorded in Florida's BB&T Center and Scotttrade Center in St. Louis.
QUANTITY VS. QUALITY
There is another route to success. The Sharks have averaged 27.6 shots per game, which ranks 12th among the 16 playoff teams, but have scored on a League-leading 12 percent of their shots. That's why they lead the NHL with 3.30 goals per game, compared to 3.15 for the Penguins, who are in second place. Is this year's Stanley Cup Final a showdown between shot quantity and quality?
Answering that question requires a good way of measuring shot quality. Unfortunately, there's no way of knowing which shots were screened based on the data being recorded, for example, nor is there any way to be certain how many shots were taken off the rush, from a cross-ice pass, or a rebound.
The location from which shots were taken is recorded, but there's not much of a difference from team to team. In fact, Pittsburgh's average shots are taken from a distance of 33.3 feet from the net, closer than San Jose's average shots (34.0), and ranks third-closest in the League behind the Dallas Stars (32.5) and Blackhawks (33.0).

It's possible the Penguins haven't been sacrificing quality for quantity at all. The only evidence on which it can be argued the Sharks are taking higher-quality shots is their higher shooting percentage. However, it's impossible to determine if that's because they're taking higher quality shots because they have better shooters, because they have faced weaker opposing goaltenders, or even because they've had more puck luck.
In the absence of any clear way to reliably determine shot quality, it makes sense to focus on the quantity of the shots. And, because it hasn't been artificially boosted by factors such as score effects and recording bias, there's every reason to believe Pittsburgh's high volume of shots is deliberate, and sustainable.
Last year, the Stanley Cup was won by the regular-season League leader in shots, the Blackhawks. If the Penguins make it two years in a row, will more teams follow this strategy in 2016-17?