geeker wrote: "I'm American and the "overblown" nuance of 1a is not unfamiliar. Back in the day, it would often be used ironically in reference to, for instance, films produced/directed by Cecil B. DeMille."
Yes, I remember that well. But I did not interpret that word as meaning "overblown" (even if you did manage to find a quotation on the Internet that called de Mille's movies by that adjective).
(Rather I took it to mean "very large" or "stupdendous".)
In support, here are the three definitions in American Heritage dictionary:
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1. Of, constituting, having to do with, or suggestive of a literary ____
2. Surpassing the usual or ordinary, particularly in scope or size
3. Heroic and impressive in quality
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