One is that's what Tomlin does with young players (Maurkice Pouncey is an obvious exception), especially those with great potential.
Another is that ever since the conclusion of training camp, Hood's development, or lack thereof, has warranted the hard-line approach.
That's the theory, at least, that's being bandied about in the Steelers' locker room while everyone wonders whether Hood will be adequate as a long-term replacement for Aaron Smith.
Such a scenario figured to be a slam dunk back when everyone left Latrobe, where Hood had looked every inch like a second-year player for whom the light had suddenly gone on.
But since then Hood has more resembled a player who had read at least one too many of his press clippings, one who was a little too matter-of-fact about his eventual rise to NFL status and stardom.
It was more of a leveling off than a regression, but an ankle injury suffered on Sept. 26 at Tampa -- Hood said on Wednesday it was a high-ankle sprain -- also complicated matters. Hood tried to tough it out and play through the ankle when the wiser move would have been to get down, get right and then get back at it.
"Your feet and your hands make you your money," Hood said. "I'm OK now."
Tomlin will seemingly be the judge of that, and the ruling wasn't favorable as recently as Tuesday, when he acknowledged Hood "hasn't had the kind of production that he would like thus far."
The previous Tuesday it had been a more direct, "I need to see more from Ziggy."
The staff, if not the media, was aware of Hood's ankle injury, which didn't become public until last week. But Tomlin apparently isn't interested in attributing any of what Hood hasn't yet given the Steelers to his bad wheel.
"None," Tomlin confirmed. "He hasn't missed a practice."
Hood hasn't missed a meeting, either, at least not to anyone's knowledge. But he admitted on Wednesday that even when he's been there he hasn't really been there. Not in the sense that the veterans are there.
"Sometimes you sit in the meetings, you're not really focusing too much," Hood said. "You gotta stay on point. Aaron Smith, he hardly smiles in meetings. He goes in there focused all the time. That's what I'm trying to live up to right now."
It's not as if Hood is perceived as having a bad attitude or to be lacking the proper work ethic or tools to get the job done.
What's slowed him to this point has slowed many a young player, especially those trying to grasp the nuances of a Dick LeBeau defense. Such growing pains are sometimes unavoidable, even for a former No. 1 draft choice.
Hood's future is still considered to be bright, always has been. But no one was anticipating that Hood's future would arrive on Sunday night in New Orleans.
It would be much less of an issue had Smith not gotten injured. But he did and now the Steelers have no choice but to hope Hood can grow up in a hurry, that a year and a half has been enough time for him to grasp and apply what he needs to recognize and execute against the Saints for the defense not to fall apart.
"Right now and maybe for years to come, I'm going to live in his shadow because of what he has done," Hood said regarding any playing time he gets in Smith's absence. "Hopefully, I can try to do my best, maybe do something a little bit different and try to step out.
"If I can mimic what Aaron Smith does I'm happy and satisfied with myself."
The Steelers would be the same.
They aren't either of those things with Hood just yet, and the clock has suddenly started ticking.