Well it is basing a lot of ideas on hypothetical technology and un-proven theories. i don't have the time to read it all as i am in work. I would say the theory(s) are underestimating just how much energy would be required to warp space in this manner (if its even possible). I think we'd need to somehow capture a few neutron stars to achieve this kind of energy. we would need a hell of a hot super conductor, about a lightyear in length,completely filled with these electron/positron transfer coils, Because these coils transferring the electrons would only be able to handle a minute fraction of the energy required. Dont take my word for it, i don't really understand to much about it. Obviously it would be cool if it was possible, but set aside the fact that current theory tells us the forces don't change, i think our problem always boils down to energy. we coudlnt harness, localise and maintain something like this with our current understanding of energy.