Practice Weak Skills repeats the same lessons EVERY DAY!
After spending weeks on Practice Week Skills and not making any progress I decided to increase my number of lessons per day from 5 to 10. To my surprise the second lot of five lessons were topics I hadn't done for weeks while the first five were familiar from previous days. I was under the impression that doing Practice Weak Skills would strengthen them so I wouldn't be given them the next day. Each lesson is varied enough that a repetition doesn't look like the same lesson which is why I didn't realise earlier.