But I want to offer up an example of how I see jargon as functional. The word distanciation in film studies refers to a process by which the film nudges the spectator back from emotional immediacy of narrative, documentary argument, etc. It has a synonym, distance, which is a perfectly simple, ordinary English word that could in fact be used in place of distanciation. After all, one is talking about metaphorical distance. So,
"The scene slowly introduces distanciating sound design"... could read... but that would be less economical.
"The scene slowly introduces sound design that metaphorically distances the spectator."
Even if one could make an economical switch, something gets lost. Distanciation immediately suggests that this process of creating distance will work in similar ways to the many other instances film scholars have pointed out in cinema. Distance does not.
Like any word, jargon contains connotations. I'd probably break down jargon's connotation into stylistic -- certain words feel French or German in their provenance -- and argumentative attributes -- we associate prior arguments with jargon words. Perhaps the worst offenders of jargon are those in which it's harder to point to the denotation than the connotation, but at its best jargon economically synthesizes the two.