If Shawn Thornton ever writes a book — which, come to think of it, isn’t a bad idea — he’s got the title all set. It’s something he’s said many times after Bruins game: “Never complain about winning.”

That’s been a familiar message from the B’s eternally optimistic winger: A win is always a good thing, regardless of how it’s achieved.

Well, that axiom got stretched to the limit last night at the Garden, where the latest sellout crowd was treated to one of the more boring and sloppy nights of hockey in recent memory. The Bruins mostly went through the motions and did just enough to handle the lowly, injury-decimated Florida Panthers, 4-1.

Those poor saps in the stands paid good money to see this?

In this 48-game sprint of a season, we weren’t supposed to see the usual midseason dog days when players, with so much of the grind still ahead, have a hard time finding the energy for a full effort.

But sure enough, here we are: The Bruins continue to win, but don’t look real good doing it. We’re still waiting to see the B’s deliver a top-to-bottom, start-to-finish sharp performance, and show the kind of dominant hockey they’ve played so often the last few years.

Man, is that 18-4-3 record ever misleading. Already down to just 23 games left before the playoffs, the Bruins are far from peak form.