Back at the start of volume 2, I speculated that the long-term plot of the comic would be the personal growth and 'salvation' of sorts of all three main characters - Alice, Ardent and Gavia. I suspect that it is going to be how the three of them inadvertently helped the others to grow as people and about the situations and mysteries that influenced that growth.
To be fair, I'm pretty sure she only used this tactic because she knew it was the only way to convince him.
I, too wonder if the way Alice handled Jeb is related to that comment about him 'respecting strength'. Depending on who it was, she might have handled it differently (but still in an overbearing way). It's just that Jeb is one of the town roughs and the only thing that really impacts on his decision-making process is the threat of force and the threat of being humiliated in front of the townsfolk.
Maybe Jeb is an antisocial type and is the leader of the town troublemaking idlers, getting away with it just because he's the biggest and strongest. Being physically crushed by a slender woman who has to strain her neck to look him in the eye would destroy that reputation for being the local top physical specimen and his position in the community and his peer group would never recover. It's
that threat, more than any threat of being physically beaten down, which will probably make him back down. Alice's reputation of being a violent, homicidal sociopath with super-strength, invulnerability and a raft of other superpowers (a sort of female Hancock) just makes the threat that much more plausible.
Headology. It never fails.