[jgg]

It took a Rudin-based analysis course, much later, for me to appreciate proofs of convergence or epsilon-delta arguments, because my H.S. calc did not have them, and the college diff-eq assumed you knew them already. The shock was painful.

I have yet to take a course that uses the so-called "terse little blue book from hell". (:

Eventually though, you learn what you need to know.

Indeed, although I wonder about people becoming discouraged about being mathematicians simply because they've been misled for so long about what's on the "other side" of college math.