One thing I got out of the article is that an alternate-reality communist economy can be more efficient than a capitalist economy, given a good objective function. The way to do it is to simulate a market economy on your central-planning computer: Simulate a network where each node models a consumer or supply chain unit. This runs the same computation as a market economy, but propagates price signals much faster. It's faster and cheaper to do an RDMA access than to wander around a grocery store comparing the price of bread to rice.
The trouble is in formulating a good objective function. Perhaps you can solve the problem of consumers expressing preferences that Cosma discusses in "The Given Assortment, and Planner's Preferences" by imitating a market economy. Each person receives a fixed salary which they spend at state stores. Since this is how the computation performed by a market inputs consumer preferences, this is the input used by the central computer in its market simulation. But the simulation reaches equilibrium much faster than the real market and its objective function is more fair than a real market (since everyone gets the same salary).
I suppose there are bigger problems with formulating the objective function than consumer preferences. Creative kinds of economic activity are important and leaders that want to hold control may not allow you to formulate the objective even if you could.