Paul Johnson was in a bad mood. As developments go, this wasn’t of the man-bites-dog variety. On his giddiest day, Georgia Tech’s coach is never mistaken for Rebecca of Sunnybrook Farm. And veteran observers know that the first scrimmage of every preseason leads Johnson to decide that his Yellow Jackets cannot win a game.

Here we note that Tech has, for a change, been picked to win the ACC Coastal Division. And that the Jackets were ranked No. 17 in the USA Today coaches’ poll. (Not since 2010 had they been ranked in a major preseason poll.) And that Tech is coming off its best finish — No. 8 according to the Associated Press, No. 7 per the coaches — since the 1990 UPI national championship.

So: Happy days at the Flats? Harrumph. As we know, Paul Johnson doesn’t do happy talk.

As to whether Saturday morning’s scrimmage yielded any injuries: “I don’t think anybody hit anybody hard enough.”

About defensive lineman Jabari Hunt-Days, back after a year’s hiatus: “Jabari’s quick, although he did some things that’ll get you killed against better people.”

About his offensive line, along which four starters return: “That needs to be a strength of our team. We need to see more leadership out of that group than we’re getting right now.”

About right guard, the one line position not manned by a returning starter: “It’s a work in progress. That would be a kind way of saying it — a work in progress.”

About the scrimmage showing of quarterback Justin Thomas: “When he watches the tape, he’s going to be upset with the way he threw a ball a little bit.”

Et cetera, et cetera. Part of what made this striking was that Johnson had been preceded to the microphone by eight of his players, most of whom spoke in optimistic tones. “That’s what I’m excited about,” offensive lineman Errin Joe said, “carrying over the momentum from last season.”

Defensive lineman Adam Gotsis: “The ACC championship is definitely my goal. We’ve been close twice. We lost by five (points) and by two.”

Thomas: “From last year to this year, we want to be the same team. There’s nothing going to change.”

Such rosy sentiments might have had something to do with Johnson’s dyspepsia. Nothing needs to change? Tech will again go 11-3 with a defense that ranked 114th among 125 FBS teams in third-down percentage and 79th in yards allowed?

The Jackets yielded 424 or more yards in six of their 14 games last season. That Tech won five of those six was a function of turnovers and its raging offense. This year’s offense mightn’t be as mighty: With the exception of Thomas, nearly everyone who touched the ball is gone.

As for turnovers: They tend not to be a constant. Tech was 14th in turnover margin last season, but check back a year. The 2013 Jackets, who also had Ted Roof as defensive coordinator, were 84th. Florida State ranked third nationally in 2013; the Seminoles plummeted to 101st last season. If opponents aren’t as giving this season, can Roof’s troops stop anybody?

Said Johnson: “We need to be better on defense. We’ve got a lot of guys who return. We’ve got a lot of depth. Toward the end of the year we became more aggressive and we created some turnovers. We won the Orange Bowl by two touchdowns. We also set an Orange Bowl record for passing yards against us and total yards.

“You can’t live like that forever. I think everybody understands that, and it starts with third down and starts with just being more consistent. We’ve got eight starters back. … We’ve just got to be better. You can talk about it until you’re blue in the face. You’ve got to see it. We’ve got to do it on the field.”

What Tech accomplished last season was stirring. But three memorable victories — against Georgia Southern, Virginia Tech and Georgia — essentially were decided by late-game takeaways. What worked then isn’t guaranteed to work so well again.

The grinch who closed Tech’s media day had a point. (That’s the thing about Johnson: He invariably does.) Last season the Jackets stepped up in class. To remain on that exalted plane, more and better will be required.