As an anarcho-fascist: I believe in decentralized autocracy which would, in reality, be inherently democratic. The decentralized, autocratic body would decide how a proper anarchist society should function. Likewise: the anarchist society would decide the choices of the decentralized authority. In cases where the authority makes bad choices, the anarchist populace will rise up and usurp the decentralized authority for another decentralized authority.
As you can see: this system would be stable, secure, and effective by virtue of constant revolution as a means of usurping bad authorities for ever better ones.