One day into the Lazy Italian Self-Study Experiment and I've discovered that my original intention to use Duolingo xp as a benchmark for my daily Italian study goals is just not going to work.
Why? Because xp doesn't really mean anything.
I mean, it means something. But it means pretty random and inconsistent things, depending on whether you get randomly-dropped xp boosts, test out of skills, or burn gems on testing into legendary skill levels.
For instance, my goal was to accrue about 50 xp every day, or about 5 lessons worth assuming the base xp value of a lesson, 10 points. Doing well in a lesson earns you a few extra experience points, which can throw things off a little bit, but it's nothing compared to the chaos an xp boost can introduce. I got one after finishing my first lesson today, so combined with the bonus xp from streaks, I ended up only needing to finish 3 lessons to meet my 50 xp goal instead of 5. And when I kept going, I very quickly approached my study cap of 200 xp without doing anything close to 20 lessons.
Basically, this is just your reminder (which I should have reminded myself earlier) that Duolingo xp is part of the gamification engine and not a real assessment of how much language studying you've done on a certain day. A combination of streak length and lessons completed per day (unfortunately not a stat I can easily find) I think, is a much better proxy for how effective you're using the app.
Anyways, going forward in the challenge, my goal will be 5 lessons, not 50 xp. I will still keep the 200 xp per day cap, though, since counting 20 lessons is hard and I know I won't count at all if it gets that high.