Although a brief examination of your comment history suggests a satirical intent in what you have written, it has (at face value) some errors. If you truly intend to build your defense for this posturing polysyallabic puffery on the foundation of subtle distinctions in meaning you would be well served by properly understanding the customary meaning of the words in question, subtle or otherwise.
Taking, as an example, the final sentence of your first paragraph: "Brobdingnagian, deleterious, autodidact, loquaciousness... are these really such strange vernacular?" we find a sentence that is grammatically incorrect, with the singular form of vernacular. Assuming a typographically damaged plural does no good, as these words are not vernaculars. We do no better with the assumption of an elided indefinite article ("are these really such [a] strange vernacular?") as the answer is trivially yes, attempting conversation using only these words (Brobdingnagian, deleterious, autodidact, and loquaciousness) would be an exercise of Cnutian futility. As the recurring problem in finding meaning in this sentence is this definition may I suggest that perhaps the primary issue is in the choice of words? I would suggest the substitution of "words" in place of "vernacular", as this recovers a perfectly sensible rhetorical question. Perhaps, in keeping with the theme of subtle distinction in word choice, "obscure" could be substituted for "strange", signifying the strangeness is rooted in rarity of use, rather than e.g. etymology.