Well, GP compared the rules against real life and decided that they are different from real life, so they shouldn't be followed.
Chess rules are also different from real life, but people don't have any issues following them.
The question whether it was “well defined” doesn't come into play here, I think: the rules in the game tell you to ignore any overrides (such as that certain vehicles may be allowed in an emergency situation). And GP decided to ignore that part.
I think interesting discussion can be had even when respecting this rule. For example, I decided that a skate board is not a vehicle but a bike is.
Lets take chess and the knight, and 2 - 1 movement rules. If there are pieces in front of the knight you pick up the knight off the board in 3 dimensional space, right?! The rules of chess only define the final end point of the piece and not the physical motion in real space to reach that location.
With this said, if you're in a professional setting, and you pick up the king and fly it around like an airplane, everyone is going to get really tired of your shit.
FIDE Laws of Chess: 11.5 - "It is forbidden to distract or annoy the opponent in any manner whatsoever. This includes unreasonable claims, unreasonable offers of a draw or the introduction of a source of noise into the playing area."
Naturally, this rule is not interpreted literally.
Chess rules are also different from real life, but people don't have any issues following them.
The question whether it was “well defined” doesn't come into play here, I think: the rules in the game tell you to ignore any overrides (such as that certain vehicles may be allowed in an emergency situation). And GP decided to ignore that part.
I think interesting discussion can be had even when respecting this rule. For example, I decided that a skate board is not a vehicle but a bike is.