"You can't go that way." instead of "Sorry I don't understand you." or "You can't.", which seems more appropriate here.What next?
>EAT BEAN
You can't go that way.
What's going on?
In the source code, Bean is word number 12, so since it is less than 13, it is considered as a direction (It is possible to climb it after planting it: U BEAN).
Since the verb EAT does not appear in the source code, EAT BEAN is interpreted as a compass direction.
There is probably a mistake by Dorothy, and a clumsiness by the interpreter.
That's all.