You might have missed the point of the rules. They are not about FIRE, or maximizing gains. They are about risk minimized investing. Effectively 'how to beat ke

You might have missed the point of the rules. They are not about FIRE, or maximizing gains. They are about risk minimized investing. Effectively 'how to beat keeping all your money in a bank account, whilst also having even less risk than a bank account'. Debt is great for boosting returns, and the risk can be managed. But it remains risky. Certain strategies are less risky if you use debt. Those strategies have a risk that is astronomically above the risk tolerance these guidelines assume.