The Lions enrolled in finishing school last offseason.

That's what we were told, at least.

Now we're about to find out just how much they've learned.

Because for all the good vibes the Lions are giving off with these frantic finishes lately, including an improbable come-from-behind victory over the Falcons in London, that's only a start.

Detroit sits alone atop the NFC North at 6-2 heading into its bye at midseason, and if the playoffs began today, it would be the No. 2 or 3 seed, depending on Monday night's result between Dallas and Washington.

But it's in November and December that this team has come up woefully short in recent years. And that's the primary reason Jim Caldwell is coaching this team, rather than his predecessor, Jim Schwartz.

The Lions were a dismal 2-14 in the second halves of 2012 and '13, and the last time they started 6-2 — in 2011 — they proceeded to lose three of their next four before rallying to clinch a wild-card spot. The time before that — in 2007 — the Lions went on to lose seven of eight. (And then all 16 the following season, but we don't need to bring that up again.)

"Last year I said 'same old Lions' because they were losing games they should win," said Tony Dungy, the former Super Bowl-winning coach and Caldwell mentor, on NBC's "Sunday Night Football" telecast. "This is the second week in a row that they won a game that they should have lost."

That's what they did a few years ago, too, when they finally ended the franchise playoff drought, stealing wins with wild comebacks against the Vikings and Cowboys early and the Raiders late in 2011.

On Sunday the Lions became the fifth team in NFL history to win consecutive games when trailing by at least 14 points one week and 21 or more the following week. They led for the final 1 minute, 48 seconds against the Saints and the final celebration against the Falcons.

"They don't quit," Caldwell said of his team, which improved to 5-1 against NFC opponents. "They're not deterred. They play with poise down the stretch. The pressure doesn't bother them. And they find a way to make plays. But they hang together so well — that's the thing that's unique about these guys. … It's a pretty special unit."

Odd decisions

Yet, that win at Wembley Stadium was remarkable not just for the second-half rally, but also the bizarre closing arguments made in the final minute.

Some awful late-game clock management — and that was one of the questions about Caldwell coming in, remember — nearly cost the Lions a chance to kick the winning field goal.

First, the Lions appeared ready to settle for a 49-yard field goal on a bad field, despite their season-long kicking woes. Then, even after Atlanta coach Mike Smith lent a hand with his own cuckoo clockwork, Caldwell decided to run a play into the line on third down with 24 seconds left and no timeouts.

At best, you figure you're going to get a "Geronimo!" fire drill for a rushed field-goal attempt by Matt Prater, who seemed only mildly aware of the plan on the sideline, if at all. At worst, you don't even get the ball snapped before time expires and the Falcons win and the long flight home gets a lot longer.

Of course, the referees bailed out Caldwell by calling a holding penalty on a defensive tackle — those get flagged once every blue moon — and the Lions were able to run the clock down to 4 seconds and kick a 43-yarder. Which they somehow rushed — and missed — and then got to try again (from 48 yards) after a delay-of-game penalty negated the play. Prater's eventual winning kick felt less like a triumph than a bad sitcom ending when it finally sailed through the uprights.

Missing pieces

But the rest is no laughing matter, and similar coaching gaffes won't be viewed as kindly. (Last year's fake field goal at Pittsburgh marked the beginning of the end, in case you'd forgotten.) Starting with the Nov. 9 home date with Miami, the next three games on Detroit's schedule are against teams with winning records. Two — New England and Arizona — are on the road.

The rest of the slate looks more manageable than it originally did, with two games against the reeling Bears — the first at Ford Field on Thanksgiving Day — sandwiched around home dates with Minnesota and Tampa Bay. Still, the Lions would do well to avoid having to go to Lambeau Field with either the division title or their playoff fate — or both — on the line Dec. 28 in the regular-season finale.

They'll have to play well without some key pieces to do so, most likely. The Lions have yet to confirm the severity of Nick Fairley's knee injury suffered against the Falcons, but if it's a season-ender — or close to it — they'll be without one of the lynchpins in their league-leading defense.

Among defensive tackles, Fairley is second only to teammate Ndamukong Suh in quarterback pressures, according to Pro Football Focus. And he's a huge reason the Lions boast the NFC's best run defense.

"That's the way things go," Caldwell said Sunday. "You're going to end up losing some guys out there on the field."

But this many?

The Lions played without their All-Pro receiver, starting running back, starting right tackle and all three of their tight ends.

Most, if not all, are expected back after the bye week. But defensively, they've already lost middle linebacker Stephen Tulloch and a chunk of their secondary for the season. And now Fairley, too?

"We make no excuses, no matter who is in there," Caldwell said.

Nor should their fans. The Lions are threatening to live up to expectations again. No excuses if they can't follow through this time.