Seems crazy to me (and a bit depressing) that doing anything for 1 hour per day would not lead to good progress! We only have so few truly free hours in a day to spend on things like this.
Oh, it has led to great progress -- when I go to China, everything I do before and after class is in Chinese. I chat with locals, order at restaurants, read street signs, and the like. That said, there's still a long way to go before fluency.
It's also known that Chinese takes a long time for non-native speakers to learn. For someone like me (48 years old, self-employed, married with three kids), I'm delighted with my progress and feel a great sense of a accomplishment. Moreover, I often meet up with foreigners who have living in China for years, and it turns out that my Chinese is better than theirs. So it's not depressing at all!
