It's not about players being fast, it's about system being fast. jackets and penguins employed from D to F breakaways and are succeeding now. the caps still do D to D passes before getting out from their own zone, that's why they are slow imho
Sure, but physical speed will always be a significant component. For one thing, getting the puck back has a lot to do with it -- how quickly you close down opponents and get to loose pucks, and get your sticks in lanes to force turnovers, etc; on offense, how much speed your forwards carry when they enter the zone, and again -- how fast they close down on defenders to prevent them clearing the puck.
Anyway, elite teams need - and tend to have - both components at a high level.
I guess you can be closer to average and still compete if you can slow the game down to your level by using physicality, size, elite cycling game. Ducks, Bruins, Kings... Well, after Ward-Fehr-Chimera came to an end, the Caps don't really have the personnel to be elite in that category.
For this season... Trotz is not gonna change his stripes, BMac is not gonna be able to significantly change the composition.. but there's always hope for some insane chemistry, somehow, and individual brilliance. With solid defense and Holtby, that should give a chance!