I would disagree to all of this 'Se demonsrative is just for show' stuff.
A lot of se demonstrative people i know are able to use Pressure very well and are aware of the dominance of power. When shtf LSE can have trouble because it's a not very stress resistant type. For ESE i think it is different due to being result type and having a good way of thinking for crisis situations.
But still, a lot of SE Demonstrative Types are not capable of violence, at least my anecdotal evidence agrees with this.
I think it is due to not valuing SE and not hanging around SE valuing people nor thinking of SE as an acceptable solution of problems and attacks on the quadra complexes.
This leads to a lot of SE demo types simply not learning violence,because they usually are very conservative types anyways and are not pulled to typical Beta quadra Gang Hooligan or Skinhead culture stuff or other Gamma types of violent environments or people.
In Alpha quadra you kill by word, in Delta quadra you enslave the people, in both an violent response is something that will be sanctioned on a democratic and individual level (alpha) or by the collective (delta).
I do think that the Se demonstrative tough guy act usually does not really work as they would like it to in the other two quaras. Surrounded by Alphas or Deltas who usually dislike violence here means being the big fish in the small pond while your tough guy act cultivated over years is not very usuefull when it clashes with someone who values Ni enough to see through it and Se enough to have fostered skills and/or the ability and quadra complex responses to lift this stuff on the level of escalation you have been implying without ever feeling drawn to it.
So i somewhat agree with your point, but i think it is more about the cultivation of these kind of abilities and not on how capable you are of cultivating.
There are good fighters of all types, i even think LSE would be a great TIM for marterial arts, but for most of them there is simply no draw to se stuff and no reason in learning it besides the socially accepted rites in their 'home' environments.