This is a multi-part question; I am asking for how this should be handled
in "Classic-compatible" versions of Traveller (Classic/Mega, T4, and
both/all three Mongoose editions).

Part the first: In the standard rules for each, is there an explicit skill
representing knowledge and skill in martial arts (as contrasted with basic
street fighting or fighting styles that are principally for competition
(e.g., boxing) rather than for actual self-defense)? I'm fairly sure that
for Classic/Mega, the answer is 'no', and all that's available is
'Brawling'. I don't know about the others, though. (For those systems where
you've got the choice, assume the one-set-of-rolls-per-term (basic chargen)
rather than the year-by-year progression (advanced chargen).)

Part the second: In those systems that do not have an explicit martial arts
skill, what skill should be used instead - and how would you recommend
distinguishing a character who has earned that skill through formal martial
art study vs. general learning-not-to-get-beat-up?

Part the third: Assume that the character has been studying a martial art,
and has some definite level of skill. At what level of skill should the
referee presume that the character has earned a "Black belt" or equivalent
recognition of skill and discipline?

(Side question: Is anyone aware of any formally-trained martial art - not
necessarily an East Asian style - that does _not_ incorporate a significant
amount of training in 'de-escalation', self-discipline, and the use of
minimal force to accomplish a goal?)

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