Mispronouncing a word only means that you read it before you heard it. People who assign a lot of meaning to this are admitting they tend to be the opposite. If they only knew how foolish it makes them look to those who understand the realities of vocabulary, they would be humiliated.
During our early courtship I, a Theatre & Speech, literature, chattering classes sort of person, would sometimes correct my wife's (massive vocabulary, then a librarian) pronunciation. After a pause of a few seconds I would ask "what's it mean?"
Sometimes it is meaningful though. When Obama said "corpseman," it meant that he had read the word but not heard it. That might not be a bad thing in a constitutional law professor. It's a bad thing for a commander-in-chief, though.