The Bruins love to talk about what a great team they have and how much character is in their room. Stir those two ingredients together and the result should be a team that plays to its potential on a consistent basis — maybe not in every game, but most of them. No team can always be at its best. But legitimately good teams will rarely be accused of a subpar effort. As anyone who’s been paying attention to the Bruins season knows, if they’re being honest, the B’s this year have played very few truly strong, all-around games. How do you define effort? What the Bruins were doing in the final half-period of Friday’s 2-1 loss to the Toronto Maple Leafs qualifies very nicely. This was the B’s reaching deep inside their souls and doing everything they could to try to win. In other words, what the Bruins were doing during that intense and wild half-period was playing playoff hockey. Nothing more, nothing less — just delivering the all-out commitment required at this time of year. So how do you describe the rest of Game 5 for the B’s? How is it even imaginable that, after two or three decent shifts to start the game, the team could fall into such a lethargic state for the rest of the first period and much of the second? It was a very familiar performance for this season. So many times, even when they managed to win, the B’s had lousy starts, or rotten finishes, or maybe had only one line going and a bunch of passengers along for the easy ride. It’s no mystery why they blew so many third-period leads: The effort was spotty — sometimes honest, sometimes not. This group seems to get complacent very easily — again, falling back on what a great team they think they are. So that’s the troubling back story as the Bruins step onto the Air Canada Centre ice tonight for Game 6 of their first-round series against the Leafs — a team that’s far from the most talented in the playoffs, but gives the impression it actually wants to win and will do everything possible to make that happen.