In the immortal words of Sybil Fawlty: "pretentious - moi?"

Many years ago, when I ran a small automobile repair shop, I had a customer named Nicholas Salgo, a Hungarian by birth, but a US citizen, who spoke more languages than I have digits (roughly ten). Trying to follow Mr. Salgo in conversation was akin to William F. Buckley talking to a kindergarten class. When a concept didn't come to him in one language, he simply switched languages. Not just the occasional Italian or French or Russian word, but whole sentences did he use. This is to illustrate that even those of great erudition may be insensitive to the abilitities of their audience, and, ironically, become poor communicators by their very linguistic mastery.