I took a course on machine learning for my masters. I had trouble understanding most of it, and a lot of trouble solving the coursework (lots of training models), because I didn't get the theory. The kid who had an insane gaming rig always had the best solutions and his understanding was by his own declaration not much better than mine, he could just train way faster so he could make more mistakes and had the better trained models in general.

One of the techniques we learned in the course, was by the account of the Prof, working extremely well, and well documented, its just that nobody really understood why it worked and people were trying to prove why it got optimal solutions.