I listened to the podcast on IEP. The podcast was from February, and IEP's stock price plunged in May. The decision on investing in IEP centers on 2 questions: do activist shareholders add value, and are the dividends sustainable. The author would not invest in IEP, because he prefers to do asset class investing, and is not particularly good at picking individual stocks. Determining if the dividend is sustainable is difficult.

The book's 10 questions are reasonable, and the podcast on Berkshire was interesting. (There is now a succession plan at Berkshire.)

There's also a book: "Money for the Rest of Us: 10 Questions to Master Successful Investing" by J. David Stein

Money for the Rest of Us Book Review, December 13, 2022
Chapter 1: What Is It?
Chapter 2: Is It Investing, Speculating, or Gambling?
Chapter 3: What Is the Upside?
Chapter 4: What Is the Down Side?
Chapter 5: Who Is on the Other Side of the Trade?
Chapter 6: What Is the Investment Vehicle?
Chapter 7: What Does It Take to Be Successful?
Chapter 8: Who Is Getting a Cut?
Chapter 9: How Does It Impact Your Portfolio?
Chapter 10: Should You Invest?
thecollegeinvestor.com - Money for the rest of US

422: This Stock Has a 15% Dividend Yield and Has Outperformed Warren Buffett. Should You Invest? February 22, 2023
"Should you invest in Icahn Enterprises L.P., a conglomerate with a 15% dividend yield and a stake in Carl Icahn's hedge fund?.. We used the process that I used at my old firm to analyze money managers'we looked at the people, we looked at their investment process, and we looked at their performance."
moneyfortherestofus.com - Carl icahn

242: Should You Let Warren Buffett Manage Your Money?, February 27, 2019
author wouldn't invest. red flags: lack of succession plan, too much AUM.
https://moneyfortherestofus.com/242-buffett/

"In May 2023 short seller Hindenburg Research released an analysis of Icahn's public company Icahn Enterprises that claims the company is over-valued due to paying large dividends using investments from new investors. In addition, the analysis claims that Icahn took out loans against a majority of his holdings and that these have the potential to be called should the stock price move downward. On the day of the release of this analysis the share price of Icahn Enterprises dropped by 20%"
en.wikipedia.org - Carl Icahn

When Warren Buffett eventually is no longer Berkshire Hathaway CEO, Greg Abel will succeed him, May 3 2021
cnbc.com - When warren buffett eventually steps down as berkshire hathaway CEO greg abel will succeed him