The biggest, most dramatic and worst overreaction an NFL head coach can make after Week 1: changing his starting quarterback.

Which is why I don't believe Bill O'Brien is ready to let go of Brian Hoyer just yet.

Now, let me make this clear. I'm in no way endorsing Hoyer as the Texans' 2015 starter. I'm also not attaching my professional name to the thought that a seventh-year journeyman - a QB who said he "let this entire organization down" during the calamity to the Chiefs on Sunday - could be anything more than a short-term fill-in at a position that continues to drag down the entire franchise. God forbid.

But O'Brien has been backing the second handpicked starter of his tenure since March. And with almost four months, 15 games and 93.8 percent of the regular season still remaining, O'Brien will look even more lost than the Texans did against Kansas City if Ryan Mallett is selected to face Cam Newton in Charlotte, N.C., this weekend.

"I'm not going to make a big quarterback announcement," O'Brien said Monday at NRG Stadium. "You'll have to wait until the first offensive play of the Carolina game to see who the quarterback will be."

O'Brien is getting good at this tired game. He used four quarterbacks last year, starting three, on his way to 9-7. Just one week into a 2015 campaign that's supposed to be devoted to at least 10 wins, he already has played two QBs. If Mallett gets the call against the Panthers, that will make six versions of Texans starters since Nov. 2, 2014: Ryan Fitzpatrick, Mallett, Fitzpatrick, Case Keenum, Hoyer and Mallett.

It was exhausting just figuring all that out. But it's true. As is the fact that the initial lasting image of O'Brien's reign isn't J.J. Watt, the Texans' rebuild, or the team that's almost good enough to beat the Colts. It's the bleep-bleeping QB position, which began as an Achilles heel and is starting to feel a little like an albatross just 17 games into a new era.

"I get real tired of it, man," left tackle Duane Brown said two days before the Chiefs game, referring to the endless doubt and criticism that surrounds the quarterbacks he's paid to protect.

No advantage gained

O'Brien could have officially stuck with Hoyer or promoted Mallett on Monday. Instead, a coach who snarled at annoying reporters less than 24 hours earlier chose to play high school mind games in the name of the incredibly overrated sports tactic known as "competitive advantage."

O'Brien pretty much knows who's taking the snaps against Carolina. He just doesn't want to say.

"You guys will find out who that will be on Sunday," said the budding White House spokesman.

Hoyer obviously wasn't good enough in Week 1. He also wasn't as horrible as all the people who've hated the idea of him for months are making him out to be.

The Texans' offensive line was as embarrassing as their overall offense through three-plus quarters. Horrendous punt coverage allowed Chiefs QB Alex Smith to stare at the end zone multiple times from midfield. The Texans' defense didn't lock in until the game was almost out of reach, allowing the Chiefs to control the clock and rhythm of the contest.

Mallett was obviously sharper than Hoyer. He also entered the game just as Kansas City was fixating on its happy-flight celebrations, then benefited from a loose defense that was notched somewhere between soft and prevent. The accuracy issues that have plagued Mallett throughout his career also returned during the Texans' final drive: There were four incompletions and an easy sack of the cement-footed quarterback.

No hint given

"Both of them have to play better," said O'Brien, intentionally grouping Hoyer and Mallett in case Panthers coach Ron Rivera's private hobby is decoding generic statements.

It's easy to forget in the media haze of the last year, but Fitzpatrick had several worse games than Hoyer did Sunday. During Weeks 3-4 in 2014, O'Brien's first starter threw five interceptions and just two touchdowns. From Sept. 21 to Oct. 20, Fitzpatrick dropped four of five games. But O'Brien didn't let go of the leash until Week 11, when the Texans' season was on the brink and the first-year coach sought a spark.

Is Week 2 the perfect time for another spark? Did the Texans go through offseason workouts, OTAs, training camp and "Hard Knocks" just to switch starting QBs after one measly game?

If O'Brien says yes, Mallett must soar and never look back.

But it also would set a weak precedent for a man who prizes consistency. It'll mean O'Brien was absolutely wrong about Hoyer from day one. And that for the last five months, the Texans' coach was really just wasting our time.