Comment by mlsu
Is it?
At the end of the day, whether it's effective or not, Duolingo sells the feeling that you are learning a language to people. Winning a competition with Duolingo means doing better at making people feel like they are learning a language -- the strategy to win against Duolingo probably involves watering down the learning even more, to better sell the feeling.
A good way to think about it is look at some organization that wants to be effective at actually teaching its employees a new language, like the state department:
https://www.state.gov/foreign-service-institute/foreign-lang...
20 hours a week of intensive instruction.
Spanish 30 weeks Cantonese 88 weeks Turkish 44 weeks
This is what it actually takes.
Yes, it takes commitment to master a language. In the case of Japanese, which traditionally takes the most weeks to master when coming from English, we made Japanese Complete based on frequency analysis to help speed up the process of acquisition. With 777 kanji carefully selected by frequency you can get 90% coverage of kanji in the wild. This is about a third of the "daily use" set of ~2200 kanji so the process is greatly accelerated. If you're interested in seeing what 777 kanji look like, I recently created a small kanji quiz game that quizzes by English meaning words [0].
[0] https://japanesecomplete.com/kanji-game.html