That would work if the energy was actually free. Instead, since it is a single market, as soon as curtailment kicks in you do not get the energy for free anymore, you get it for the price you pay for the gas plants that replace the wind generation which can't be transmitted.

This also doesn't change if you consume all the energy at the place where it is produced, since you still need to supplement the normal load with gas. There's only two ways out of this: split the markets, or build transmission.

Oh well.