If any self-respecting investment bankers had been asked six years ago to name the greatest financial innovation of recent times, they would probably not have hesitated to name the collateralised debt obligation – a clever structure based on thousands of chopped-up mortgages and mortgage-backed securities.

The demand for the high, supposedly safe, investment returns that came with CDOs allowed them to grow stratospherically in the decade up to 2007.

Today, even the bankers who made their millions in that business are coy about letting the discredited three-letter acronym pass their lips. The popularity of CDOs in turn fuelled growth in the underlying loans, many of them ultimately concentrated in high-risk subprime mortgages to poor Americans who were soon struggling to keep up repayments. As anyone with even a passing interest in finance will know, this was how the seeds of the financial crisis were sown. Simple securitisation, repackaging loans into new bonds, is edging back into fashion as fund managers seek investments that will generate a little income amid stubbornly low interest rates. But the CDO – and the more abstruse derivatives it generated – is certainly not high on many people’s best-inventions list any more.