Actually you're both right; however it's the Second Vermont Republic that thinks they can secede via the mere popular will of Vermont citizens, while the Free State Project thinks that they can make a difference without state sovereignty-- i.e. they have no intention of challenging federal authority over the state.
I personally disagree with both of them, since 1) current federal policy forbids secession, and 2) history proves that it's impossible to achieve state-freedom without the right to secede (and in fact I've had this disagreement with the FSP for some months now on their forum-board). In fact, this is what led to the Civil War, i.e. federal exploitation of under-represented states; and now that secession is verboten, state freedom is for the Byrds.