duolingo seems to be having problems updating progress when you are strengthening a lesson learned
I noticed it too. I've done 4 lessons today (None that required strengthen). Redoing the lesson, Strengthening without and with a timer will only refresh a few words. My first time no word was refreshed. 4 Lesson, 13 words refreshed. I'm doing this on my computer too. I typically have at least 13 words refresh in a lesson.
Duolingo no longer tells you what skills you've strengthened in the website update. You could have strengthened a skill and Duolingo will never tell you.
I think it's just the new (and IMHO horrible) strengthening algorithms. :sigh:
I am having this issue too. It does seem to strengthen it, but takes time for it to be shown as strengthened on the tree. Strange, as I read somewhere that the new site was supposed to be faster.