This team has overachieved, the window won't be open until Chucky becomes the no.1C (or we trade for one).
What these PO's have shown us is that Price & Subban can absolutely lead this team to a Championship.
I don't think we've overachieved. 2010 was an overachievement. Halak played like a god, and Cammalleri was on a path to the Conn Smythe. Neither have been able to reproduce the way they elevated their games during those series (While I don't doubt that Cammy could still be a good playoff performer on a good team, I doubt Halak will ever come close to his level during that short period). Yeah, there were a few other good contributors, but that 2010 team was a so-so team who pulled a rabbit out of a hat.
This year, you've got Bourque and Briere who've played better than they have all year, but overall, this is just a really solid team. Carey is a world-class goalie and he's playing like one. PK is a Norris winner, and he's playing like one. You have guys like Vanek, Pacioretty, Desharnais, Gallagher who are all excellent forwards producing well. Aside from Bouillon and Murray, our defence is solid, and even at that, Beaulieu has stepped up to take a big role.
It definitely looks like the window is open, but I do think that this whole streak without injuries (until Price) was a little... lucky. Without a top guy like Vanek (or another playmaking FA forward), I think that this team would need to go injury-less for the entire playoffs to reach this point, or farther next year. And that's a lot to ask. But whatever happens in these next few games, the future definitely looks good for the Montreal Canadiens.