This is a great essay! I highly recommend "A Random walk down wall street" to anyone thinking about investing.
The thing that confused me about Random Walk down wall street was that he spends the whole book explaining that all strategies for investing are useless, and then in the last chapter he gives out advice for investing.
I think he included that because some people just won't listen and they really really want to pick stocks instead of invest in index funds. I think he had to acknowledge that those people exist, but try to mitigate that desire by writing the first 400 pages about sensible investing.
Wasn't the gist of his advice to not try to predict prices and instead just invest in index funds? That fits in perfectly with the rest of the book.
The Michelle Bach situation is interesting. Assuming the facts are true, she in fact arranged an interesting although slightly unreliable option for herself here. Had the price gone down, she could have tried to divest her holding to the customer and made them wear it.