Bay-area buddy Simon Quellen Field (and well known fiddler of magnetic things) suggested that motors could turn the sails, instead of the 2:1 gear. Of course they still turn at the same speed, in accordance with the 2:1 ratio - but no pulleys, chains or turning shafts.
As the main generator is making electricity, there is ample to power two smaller ones to turn the sails. The two smaller motors would only be under modest load as there is little torque due to the sails being symmetrical around an axis.
Its even possible that the whole contraption could recover adequately after the wind (or fluid flow) drops to zero. As there is bound to be some movement causing a random rotation, to create some modest electricity to allow the sails to adjust to their optimal positions.
This would be the case even if the wind changed direction.
It may be that some local battery, capacitor or fly-wheel storage would be needed. Or (or all things) a solar powered battery could be modestly sized.
Very clever Simon.