jargon helps in the communication as long as the people involved check very carefully what they are doing, saying or writing. Well, I guess everybody tries.

Yes, I never suggested that the communication is good or that it actually takes place, but that most people are trying to communicate something. Even purveyors of the most obfuscatory prose are trying to say something. I may not like or be buying it or even be swayed and persuaded by it, but I willing to give them my attention, at least until I determine what it is they are trying to say. More often than not, I simply find that people discount what somebody may be discussing because of some jargon creeping into the dialog. I do think it is important not to take jargon for granted when discussing something with somebody who is not in-group, but whether to explain terms as one uses them or to try to paraphrase the terms is a strategy for another thread.

Ceci n'est pas un seing.