"Certainly nothing beats a good book, but often a good lecturer can give some intuition or motivations that are not customarily written down."
You are correct on both points. Early in my learning, I found both points to be important. And, for a beginning student, both points can be crucial: Without the second point, it is far too easy for a student to get into some not very good material or into some good material but, still, lost.
Eventually I got away from your second point.
Still, there is a version of your second point that lasts: For research, seminars and conferences are good, fast ways to keep up, see the forest for the trees, pick new research directions, etc.
When my company is successful and I retire, I will return to mathematical physics and, maybe, attend research seminars in, say, Boston.
You are correct on both points. Early in my learning, I found both points to be important. And, for a beginning student, both points can be crucial: Without the second point, it is far too easy for a student to get into some not very good material or into some good material but, still, lost.
Eventually I got away from your second point.
Still, there is a version of your second point that lasts: For research, seminars and conferences are good, fast ways to keep up, see the forest for the trees, pick new research directions, etc.
When my company is successful and I retire, I will return to mathematical physics and, maybe, attend research seminars in, say, Boston.