The constant change up of lines especially on the PP has to stop. Blashill has plenty of options at forward he needs to find something that will stick
I see what you're saying to a degree. Just a slight counter-point on this, more to your referencing the PP. In this day and age of technology, teams have video on opposing teams at their fingertips and even have a full time positions with "Video" in their job title (Wings have two). They even have video on the other teams via their iPads on the bench during games. Changing lines up and giving your team, or PP unit different "looks" at times can be also part strategy. I've heard Joel Quenneville state this a few times in interviews over the past few years. Even back 10 years ago video and opposition analysis wasn't nearly as developed as it is today. So, when the other teams know your tendencies, know where you break down, know how to better open shooting lanes, etc...it makes it much easier to develop a winning strategy as a team.
I'll be clear though, if you have a top 5 PP unit, or top 5 line in the league, you're not, or very unlikely to make any changes. Understood..."beat us if you can". But the days of a team jumping on the ice and having a "rough idea" of what the other team is going to throw at them and developing an effective strategy on the "fly" are over.