Talking about physics is really misleading when dealing with a magical fantasy world. When most people hear the word "physics", they tend to think "objects in motion stay in motion until acted upon", etc.
We've got a LOT of evidence that 'physics', as we understand it, does not exist in Erfworld. E=mc2 probably doesn't apply in a world where money can be converted into units and buildings. "Conservation of Energy" in our world might become something like a law of "Conservation of Shmuckers" instead. Animate bodies cannot cross hex boundaries if they're at zero (0) move, but inanimate objects can (Rob has mentioned that status notes were passed from hex to hex in a post).
So what happens if you build a shell big enough to fit a person in, seal that shell, and launch it across a hex boundary? We don't know. If it's some sort of mind control that prevents units from crossing hexes, then the shell would sail through. If it's a 'force field' effect, the person in the shell may be crushed against the wall of the shell as it passes through. But talking about 'physics' when magic is a known quantity is misleading at best, and confusing.
What might be easier is to keep it simple: Is the world internally consistent? If a certain process is established, does the world behave logically based on that process?
For example, we know that Erfworld behaves as a 'game-like' world, and units pop fully-formed. There is no childhood. Is there aging? We've seen units that look older, but did they pop at that age? Does the physical appearance of being older simply imply a higher "wisdom score"? Is wisdom / intelligence / etc. a hidden score in Erfworld?
Or do units really age? There's a song that talks about 'the turn you decay' - are they referring to an aging process, or does 'decay' refer to when a corpse de-pops?
Speaking of decay, is there bacteria in Erfworld? If the world is created, Evolution clearly has no place, so there's no reason for there to be single-celled organisms. Trying to figure out fundamental assumptions can lead to a lot of crazy theories.
Unlike Parson, we can't actually experiment in Erfworld. We can simply observe, so most of our conjectures will be nothing more than arguing for the sake of arguing, which is still very enjoyable, I'll grant you. But it ends up being more like a religious debate attempting to analyze scripture - "What did the gods intend by this statement?" Fortunately for us, our 'god' is distant, but still responsive.