I've just come back to the site after not using it for a couple of months and I'm unsatisfied with the new formatting of the lessons.
With the old format, you could view all the lessons in a topic on one page. Videos on one side, lessons on the other. When you clicked on a lesson, it would open up a mini window within the page. When you finished, the window would close and you could click on the lesson again to restart it. It was also easy to search for uncompleted lessons or videos since everything was spaced out.
The new format is much more clunky and difficult to navigate. When you click on a lesson, you're taken to a completely new page. Videos and lessons are clumped together in a scrollbar on one side of the page, which means I have to sift through more things to find what I'm looking for.
Furthermore, once you're done with a lesson or video, it takes you to the next item, which means that in order to restart a lesson, I have to click to the next item and then click back to the one I was on. It would be nice if there were a "back" button or a "restart" button so I could redo a lesson if I got a less-than-optimal score or wanted to keep practicing.