Ah, Caenus my dear friend. You're assuming. Your example is correct, but you didn't take into account that 3d objects, might have 4 dimensions. Length, Width, Hiegth, Mass. I'm making the (most likely incorrect) declaration that the force of gravity is a vibration of the 4th spatial dimension, and that the phsyical manifestation of the 4th dimension is the property we know of as Mass. Just like a 2D bug could see the effects of height of a 3D object, we see the effects of the 4th dimension, namely mass. So, Mass has a true meaning in the 4th dimension, and has effects on 3D ships traveling the 4th dimension.
Now, this is most likely 99% bullshit, but that's what I've been seeing.
[EDIT:]
This all being said, the math would basically be adding a 4D vector to your 3D vector (velocity). So, when you're hit by these eddies, your mass will change as well as a directional vector being added to your ship. As a second note to this, a computer is key to travelign subspace. It makes piloting work just like you'd imagine. However, without the computer, you will either kill yourself, or get lost, edning up who knows where in realspace. Perhaps a NorAellian could pilot without a computer (some do), but they can visualize in 4D.
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