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?
It's a bit like music. You can look at a lyrics site and learn all the words for lots of songs, but unless you also learn the tunes that go with them, you don't have the context to sing the songs. The message means you've learned x% of the words in a typical article in the Immersion section, but Duolingo can't teach contextualisation of those words directly in any but the most restricted senses. This is part of the reason the Immersion section exists, because it can teach context indirectly.
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. ;-)