Chapter posted above spoiler below:
Toriko went from not wearing vest to wearing it, it was enough to give away that it was memory. The limit seems to be energy and not just mental focus, but this is the limit to the amount of times you can do it, the limit to the actual power probably lies somewhere in G-cells. If they are conscious, they should be able to interact, or else all of these super natural ability to sense threat and intimidate without doing anything would not make any sense. For now I think the limit is the strength of G-cells, so if a person has both strong mental power and has eaten tons of good food, they should be powerful.
This will also help cement why these old people are extremely powerful, both their cells and their mental powers are on higher level and they don't depend on age or physical condition. Food pressure and food honor make sense for good and bad guys, but shouldn't even Starjun have this power? Also why was Toriko taught a pseudo intimidation by specific character, it seems everyone should have it.
edit: Oh and you actually have to believe it, so it's both good g-cells and tons of energy and then you need to be convinced, which is a nice mechanism against someone being hypnotized into becoming the strongest.
I think overall it's a shity concept if overused, I mean if it's like intimidation it's nice, but if overused we will have bunch of genjutsu battles. But based on Torikos last attack it seems he uses it as diversion because the other person gets some time to dodge and then he moves in, so it can really work out as throwing stars do in naruto, useless but nice combat mechanism.