That view is echoed around industry. "It's not enough on its own to bring these markets back," said Richard Hopkin of the Association for Financial Markets in Europe. "The capital rules need to be changed to make it easier and cheaper for insurers to invest."
Insurers, holding more than 8 trillion euros of assets, are reluctant to join the debate in public but, privately, some executives express concerns about the risks.
This bodes ill for the ECB's chances of breathing new life into a market that withered to 180 billion euros issued last year, about a quarter of its size in 2008.
The market in the United States rebounded to 1.5 trillion euros last year.
Read MoreEuro area is 'stuck in a rut'
Inside the ECB, few are predicting a similar splash for a plan that was championed by Draghi after he studied Britain's funding-for-lending programme.
"Some people know that this will not work," one source familiar with the matter said recently, referring to buying ABS and a more secure variant known as covered bonds. "It's too small and the problem is much, much bigger."
Some at the ECB believe that if its impact is small, it could reinforce Draghi's message to reluctant governments that they too must pitch into efforts to save the economy by reforming or investing.
But Draghi has had little success in convincing governments to back the purchase plan with guarantees for riskier ABS tranches, a step that would add a seal of security. The suggestion has been flatly rejected in Berlin.
"I fear that there are big dangers," German Finance Minister Wolfgang Schaeuble said last May, in words that still sum of the feelings of many in Berlin now. "My warning of big liquidity risks holds for Europe and the whole world."
Read MoreOn the brink:Financial crisis timeline
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