Gotta say - the projects in the book made all the difference for me. It's one thing to read their high level, notation-heavy chapters, but I found that working through the exercises really solidified everything in my mind.

That said I got pretty lost near the end. I want to go back in a year or so once I have a bit more math background.

I hit a brickwall too, even though the idea behind Lagrangian Physics felt so natural to me, I still trying to re-read books about the subject on a regular basis (very often it's all it takes to get started on something).