It is too easy to make things up in macroeconomics without any ability to prove their validity. You can speculate on big things, but there are too many factors involved to track and validate their real impact on the outcomes.
If you understand math and logic, you have the basis for understanding the scientific method, which means you can derive knowledge and learn anyone knew. If you can understand the subject, then you can also separate truth from falsehood, and to form your own opinions around them instead.
To get good at something, you have to practice, and by reading slow you can really grasp the meaning of the context and attain understanding, as opposed to flying through a bunch of books without ever realizing their meaning.