Even if we can agree that jargon is absolutely necessary, we still can't help but be annoyed by it.
Every profession has jargon: specialties and sub-specialties are shot-through with special terms like “endoplasmic reticulum” or “moment of inertia” particular to them.
Too often, these are otherwise normal words set to specialized uses. I was appalled at the way some coworkers of mine felt the need to police the word “coaching.” I took umbrage at coaching having been corralled from general use to plod only in the confines of a specific discipline.
When jargon finds its way back into general use, as necessity or happenstance sometimes dictate, we view these terms two ways: both as signs of an expertise deserving of respect and as weapons snobs use to make the rest of us feel stupid.
But we should probably cut the jargon-user a little slack: she may be so immersed in her own work that she just forgets that not everybody knows what she knows. And anyway, jargon is good at summing up complex ideas without the user having to explain them over and over. By using the term “volumetric efficiency,” an automotive engineer saves time and communicates efficiently with other engineers.
It's when jargon is used to confuse and gain power that we must be wary.
The term “the invisible hand of the market” covers up the real chaos of lives and livelihoods being swept away as people struggle to adapt to new ways of making money.
The use of jargon outside of a specialty, then, might properly be an opportunity for learning, a chance to really discuss the issues the term implies, and not a power-play or just another chance to talk past one another.