No. He is referring to CDOs, which were packages of low-quality loans, which could have high-quality loans issued against them. For example, if you have ten $10

No. He is referring to CDOs, which were packages of low-quality loans, which could have high-quality loans issued against them. For example, if you have ten $10 loans, and expect half to pay off with $11, and half to default leaving only $5, you could have a very high-rated loan entitled to the first $25 of payments on any of those loans. The problem in this case is that the underlying loans were deteriorating in quality, to the point that even very secure loans against them ended up doing badly.