Duolingo's claim that we're 52% fluent should be clarified. We're more like 52% fluent in reading French but not in speaking or writing. For example, about 50% of the time we can read the French that's peppered throughout Nabokov's oeuvre. For example, in Transparent Things, when Armande, who had a grain de beauté, setup a rendez-vous with Hugh prior to their subsequent marriage, she told him, "Now listen, tomorrow I'm occupied, but what about Friday-if you can be ready à sept heures précises?" (43)
Erard related from Krashen in Babel No More: The Search for the World's Most Extraordinary Language Learners that: "[Language] [a]cquisition happens [...] when we understand what we read or hear-not when we speak or write it, memorize vocabulary, or study grammar." (102)
Very recently, we watched all fifty-two episodes of Yale University's French in Action. Interestingly, we didn't understand 50% of the dialogue, but we understood over 50% of the transcripts.