Talking about my old optical spectroscopy class brought a couple of other things to mind. One of them is that I have never used a good solid 95% of the material I learned there, ever again. Not even once. I worked on a big ol' honking normal coordinate analysis for a class project during that time, and looking back at it, I'm shocked to see the stuff in my handwriting. I supposed there must have been some benefit to learning all of this material, but it is a benefit that time has managed to obscure.
The main thing I took out of the class was the incident I spoke of earlier in the week - hitting the wall of what I had already learned or could pick up on the fly. I'd been warned for years, while growing up, that I was going to have to buckle down and study someday, which news I absorbed in an abstract sort of way. I thought that the prediction had come true in college, but in those courses I could still show up unprepared and understand what was going on. This spectroscopy class was a different order of experience, and a useful one. Fortunately, I left academia before running into the experience of a subject that not only could not be understood in real time, but couldn't be understood after long and careful thought, either. I am reliably informed that they're out there.
The other result of the class was the following work of art, which I composed one day in lieu of doing the assignment. I posted some of this a few years ago, but many readers will not have seen it. It is, of course, a parody of Lewis Carroll's White Knight's song from Through the Looking Glass, which is in turn a parody of Wordsworth, who seems to have tuned up many parodists to concert pitch.
He waved his hands and asked me why
Some peak would polarize
But I was thinking of my lunch
And looked up in surprise.
He then showed me a diagram
And I found to my shame
I didn't know what good it was,
And couldn't say its name.
And if now I chance to put
My tongue in super-glue
Or madly cram my chiral foot
In its enantiomeric shoe,
I weep, for it reminds me so
Of that old class I used to know,
Of ligand fields and planar nodes
And symmetries of normal modes.