I have completed my Polish tree, with a duration of 3 days and 1 hour. I've could've been the first user to reach level 11 in Polish and completed the tree, but br0d4 earned the title (behind him is Viersch). Well, at least I'm the third user to reach level 11 in Polish and completed the Polish for English tree.
Is anyone else Level 11?
Congratulations to you, although it is pretty invaluable to me that you finish in 3 days, without learning anything useful. My approach is to learn slow and steady and use duolingo as a support to my learning process. Competition seems sorry, but a bit pointless to me. Also same goes to XP people here, it is stupid, I can complete the tree on languages I already know of and Bazinga, it is 20,000 XP which is a fault or cheating in my eyes. Anyway, nice to know someone can do it.
For me I could probably get through the tree quickly, because I could already read Polish and get the general gist of it, I knew the nominative forms of a lot of words and the base of a good number of verbs, so I didn't worry too much about Cases and Genders.
It's a whole other story once you have to start translating more English sentences into Polish, I now spend a lot more time just keeping all the skills I've done golden than advancing further in the tree.
The first few days I was flying through it, now I'm lucky to have the time to clear one row of the tree in a day, because I always try to make sure everything above is still golden before advancing.