That he did is charged by "Hayek" in the freshly released "Keynes versus Hayek: Round 2" at http://www.youtube.com/watch?v=GTQnarzmTOc , put out by Russ Roberts and John Papola, with backing from the Mercatus Center at George Mason. Like its predecssor, it definitely sides with Hayek, but is also highly hilarious, with pretty much anybody able to enjoy Papola playing Bernanke handing out wads of cash to bankers, and some other goofy stuff, such as libertarian anarchist Ed Stringham eagerly interviewing "Keynes" after he is declared the winner in a boxing match after being knocked down by "Hayek."
However, I do find it disturbing that increasingly Austrians and some others have taken to charging Keynes with having supported "central planning," as indeed done in this video. Is this correct? I think that the answer is largely "no," with it certainly being that answer if one means by that command central planning of the Soviet type that Hayek criticized in his Road to Serfdom (which Keynes praised, btw, when it first came out).
I think the strongest evidence for Keynes supporting central planning comes from two sources, which I shall quote. The first comes from his 1920s essay, "The End of Laissez-Faire," which has been identified as the inspiration for the movement for indicative (non-command) planning that was seen after WW II in such countries as France, Japan, India, South Korea, and some other places, although not UK or US.
After noting that uncertainty can lead to inequality of wealth and the unemployment of labor, he states: "I believe that the cure for these things is partly to be sought in the deliberate control of the currency and of credit by a central institution, ans partly in the collection and dissemination on a great scale of data relating to the business situation, including the full publicity, by law if necessary, of all business facts which it is useful to know. These measures would involve Society in exercising directive intelligence through some appropriate organ of action over many of the inner intricacies of private business, yet it would leave private initiative and enterprise unhindered." (p. 318 from Essays in Persuasion)
One can argue that Keynes is offering a hopeless contradiction when calling for this "directive intelligence," probably the closest he came anywhere to command, with his simultaneous limit on that regarding leaving "private initiative and enterprise unhindered," this latter certainly not fitting with the full-blowin command socialist model at all.
Regarding the information gathering, well, of course that is now generally done in most higher income economies, and many have argued that this was the essence of the indicative planning operations carried out in many countries, when they worked at their best, as some claim was the case in France in the 1950s, when businesspeople needed some sort of external push to revive their animal spirits, to use Keynesian language, and that seeing projections of demands by others helped provide this.
The other passage that some have pointed to as possibly suggesting a central planner tendency by Keynes comes from the final chapter of the General Theory, p. 378:
"Furthermore, it seems unlikely that the influence of of banking policy on the rate of interest will be sufficient by itself to determine an optimum rate of investmenet. I conceive, therefore, that a somewhat comprehensive socialisation of investment will prove the only means of securing an approximation to full employment; though this need not exclude all manner of compromises and of devices by which publich authority will co-operate with private intiative. But beyond this no obvious case is made out for a system of State Socialism which would embrace most of the economic life of the community."
One can argue again here that Keynes is setting himself up for some sort of impossible contradiction, and Hayek may well have argued that such control of investment would lead to his road to serfdom slippery slope. However, it is clear from later passages that what Keynes had in mind was ultimately the control of the aggregate of investment rather than of its specific forms or details.
These almost certainly provide the strongest evidence for Keynes supposedly supporting there being a "central plan." But it looks at most, putting the two together, like one that involves lots of provision of information and data along with some sort of control of aggregate investment, while leaving most of the decisions up to "private initiative." This hardly constitutes a "central plan," and certainly not one of the sort that the actually existing Hayek criticized. The fictional one in the video should have spoken more carefully.