The first shaky principle is that if the return on these bonds is highly correlated, so that they all default at the same time, overcollateralization is not much help. By contrast, if the returns are uncorrelated, it is extremely unlikely that they will all default at the same time, making overcollateralization sufficient to guarantee a safer return.
首项不合理原则是如果债券收益高度相关并同时出现违约，则超额抵押不会产生多大益处。 相反，如果各项收益互不相关，那么同时违约的可能性就很低，在这种情况下，超额担保足以保证更安全的收益。