You can read x% of all articles- unrealistic?
Is the figure of " you can now read x% of all spanish/german etc articles!" a bit far fetched. I'm just over half way in Spanish and I can apparently read 50.6% of all articles?
Yes, but it shows that you're in the starting point. You know basic words meaning. Over a time you will learn more when you'll discover that there are more meanings. How much you understand can't be measured here. Maybe tests of reading comprehension can help to measure that, but I don't think that is the point of the website. I think Duolingo does a great job to start with a language, but still - it won't do the work that you have to do. Even the best site or application won't teach you. It might only give you tools and in this Duolingo is really perfect.
I think their algorithms are a little off, as well. I'm currently in the "Adjectives 2" lesson in Spanish, and my Percentage jumped from 60% to 90% in the span of a few exercises.
I may know a few more adjectives now, but there's no way I could conquer 90% of Any article at my current level! (well, maybe a book intended for a 2 year old) :-p
I always take it with a grain of salt.
Update: Just finished Adjectives 2, and.... "You can now read 95% of all real Spanish articles"
More grains of salt, please. ;-)