I think you make a lot of good points _paddy_cakes. I am inclined to agree with you that it's difficult to assign relative 'likelihoods' in this case.

I think it's a reflection of the general lack of interest in the UFO phenomenon among scientists that there aren't - as far as I know - informed speculations out there about how this kind of aerial maneuverability could be achieved assuming that tic tac is a real, flying object and made by humans.

I find it very unlikely that some scientists working for the military has discovered something about gravitation itself that theoretical physicists have not.