And he has written an article with Labour's Chuka Umunna for the Independent: The deafening silence on the Government's industrial strategy is ominous.
For many years Vince has been the Liberal Democrats' preeminent voice on economics, yet you have to ask if we made the best use of his talents in government.
One of the party's weaknesses in government was that we never developed a distinctive Lib Dem position on the economy.
Danny Alexander was catapulted into the Treasury following the rapid resignation of David Laws. Because he had no particular knowledge of economics he was at first able to do little more than mouth slogans about "clearing up the mess left by Labour".
Later he became quite an assured performer, but by then it would have been too late even if he did have something interesting to say.
David Laws could have been that distinctive voice - his first Commons appearance at the dispatch box was immensely impressive. But given that his contribution to the Orange Box called for the National Health Service to be replaced by a private insurance system, how far his views on the economy differed from those of the Osbornite orthodoxy is open to question.
So should Vince Cable have been chief secretary to the Treasury?
Someone of Vince's seniority having his own department to run seemed fitting when the Coalition cabinet was appointed, and it was understandable that the reshuffle following David Laws' resignation was made as limited as possible.
But there is an important message here.
If we Liberal Democrats ever find ourselves in power again then our most powerful voice on economics, if he or she is not the party leader, must be in the Treasury.
Later. There is an enlightening interview with Vince Cable in the Guardian.