Why Dick Dastardly never wins
Before the first tile, there are memories. The most useful of them all comes from a cartoon: in Wacky Races, Dick Dastardly and Muttley are the only racers whose entire strategy is to harm the others. Traps, wrong turns, bombs — and they never win. Not because the script punishes them: because they stop to sabotage while the ten others keep driving.
That became a design rule, and I think it is the most important one in the game. I forbade nothing. An apprentice has two actions and one tile move per turn, and whatever they spend for the sole purpose of hindering a neighbour, they do not spend on themselves. WizoCat does not forbid sabotage, it bills it — and the bill is their own diploma. A ban can be worked around; a cost cannot.