Math is “regular” enough that you can get away with using math at a higher level than one understands. All “practitioners” are using fringes of math they barely understand, which is ok — book says Theorem XYZ guarantees. But that’s also where your mathematical growth is stunted. Learning “higher math” is always standing back a little.

The epitome of this is the feared Real Analysis class where many people realize they’re pretty much incapable of understanding high school calculus. But it keeps happening.