Alas, William Conway, co-founder of the Carlyle Group, speaks from experience.

Carlyle Group co-founder, William Conway, said in a leaked email to investors that lenders, including those who work with Carlyle, are making “very risky credit decisions” when providing financing for buyouts. ...

“Frankly, there is so much liquidity in the world financial system, that lenders are making very risky credit decisions. This debt has enabled us to do transactions that were previously unimaginable, and has resulted in generally higher exit multiples than entry multiples,” he said.

Deals he cited as “unimaginable”  included that of car rental group Hertz. Carlyle paid $2.3bn in equity, with two other firms contributing the same amount, but borrowed a further £12.3bn to acquire the company. Another example given was the $18bn acquisition of semiconductor business Freescale last September.

Although he predicted this availability of debt would continue for the next 12 to 24 months, and admitted he could see no catalyst for a change in the liquidity of the debt, he acknowledged, “The longer it lasts, the worse it will be when it ends.”

Of course, if you read any book about financial markets history - any one at all - you'd realize the same thing.