At MacLaren's, Carl tries to kick out Ted and Barney so he can close. They tell him they're waiting for their dates, and ask if they can close for him. Carl says they can't, because they don't know the first thing about running a bar. When Barney says, "Serve the hotties first," Carl's impressed and relents, giving them the keys. They're ordered to shut off the lights and lock up as soon as their girls show up. In order to explain how much it meant to him and Barney to be left in charge, Saget!Ted narrates a flashback in which Ted and Barney have a beer-fueled conversation at Ted's place, and in which Ted declares, "We should buy a bar." Barney is all over that. And when they do, he wants to name it Puzzles. "People will be like, 'Why's it called Puzzles?' That's the puzzle." And I know they're drunk, because Ted agrees that it's a great name for a bar, and that when they have their bar, they will never have last call. Saget!Ted then compares, "We should buy a bar," with the other ill-advised, five-word sentences every man says in his life: "I can jump that far" (cut to Marshall, on a rooftop); "I'm gonna win her back" (Ted, of course); and "I can trust you guys" (Carl, tonight at MacLaren's... oops). Saget!Ted says they'd come to regret their "We should buy a bar," they just didn't know it yet.
Later at MacLaren's, Barney and Ted make like they're Tom Cruise (in Cocktail, not in couch jumping; don't be glib), in an otherwise empty MacLaren's, as the Beach Boys' "Kokomo" plays, because this is a musical montage, y'all -- or, as we like to say, "filler." But it's cute filler.