Legendary fund manager Li Lu (who Charlie Munger backed) once said, ‘The biggest investment risk is not the volatility of prices, but whether you will suffer a permanent loss of capital.’ So it seems the smart money knows that debt – which is usually involved in bankruptcies – is a very important factor, when you assess how risky a company is. We note that James Hardie Industries plc (ASX:JHX) does have debt on its balance sheet. But the real question is whether this debt is making the…