I believe he was referring to what would happen if your ship landed engine-side down. That really isn't how it's intended to land, but that still isn't an issue because the weights are generally denser than the ground.
What, precisely, do you mean by portal ship?Do you mean the semispaces I use to control the weight in the fluxes or the portal? Because you can't really have a portal ship without a portal... How would those things be accomplished without a portal?
I have. Look at my post at the top of this page.... you have yet to say a model as effective as this with as few different principles. This isn't the best thing that could be made. Its the best thing with as few different principles at as low a level as possible.