I'm talking about worker cooperatives operating in a market economy, not about state-run enterprise and artificial markets (i.e., the Soviet model). The latter has the worst of both worlds, in my opinion.
There is no one "Soviet model". There are several models: War Communism, NEP, "Stalinist" economy, Khrushchev Revisionism, Brezhnev Revisionism, and Perestroika.
I'm talking about "Stalinist", obviously. But it had co-ops that operated within market economy (eradicated in late 1950s by revisionists), so I'm not sure what you mean. Kosygin reforms?
Planning has more signalling mechanisms.
But markets are more immediately responsive (both to new needs and to changing priorities),
How? Explain to me what mechanism Market has, Planning doesn't.
Yes, but he's continuously producing, so quotas and sales models can be continuously changed.
Plans, by their nature, must cover a distinct set of time
Nope-nope-nope. First and foremost, plans are priorities. You have general goals (build industrial cluster that will produce something; which means you need hydro plant there and nuclear power plant here;), the rest are guidelines. It's obviously more complicated than that, but it's not some inflexible time-table you have to follow to the letter or everything goes kaput.
it's not going to be as quick to change, especially if your planning was done on a directly democratic basis.
Democracy sets goals and gives promises ("we promise to produce that much of this stuff, so you can count on us", for example). The rest is job of managers.
No, it doesn't. Markets use price. Planning doesn't have that.
Planning can use price. It's just inefficient to be bound by price alone (which is the curse of market). Which is why markets go belly-up without finance (it exists to circumvent problems price causes).
the ones that allow to predict things that will happen in the future
Impossible, both as a matter of physics and as a practical reality.
If I order car next year, producer can be certain that he can sell car to me.
Then can you elaborate on the planning model you have in mind?
There isn't one set "planning".
First phase would be NEP-like State Capitalism with pre-existing corporations being managed by state and overseen by people's commissars (grass-root investigations - RabKrIn, if you know what I mean). That could take 5-10 years, depending on circumstances. It should be easier to manage today, but we have less actual (non-cultist) economists.
Second phase would be actual Socialism (what I often call "Soviet model", implying apex of USSR economy - which is generally referred to as Stalinist economy; hence my icon), with centrally-planned economy doing the heavy lifting (industrial goods, infrastructure, most of research, medicine, some basic consumer goods). Co-ops are a minor factor (overseen by state; mostly consumer goods; 5-10% of economy). That could last 20 years easy. Probably more, since we don't have a concrete idea on what should be done after, other than "create more productive forces".
Third phase would be transition to actual Communism, with more and more goods being freely (or "socially", so as to differentiate from unreasonable demands) available.
Give me a little credit, I'm not one of those retards.
This is Holla Forums.
Yes. Read Lenin.