Excellent post, as usual!!  Actually, I thought the lesson of the story would be something like-- 你偶尔应该倾听别人的意见, since setting off in the right direction, and continuing in it, often isn't within the province of the traveler alone.  We need advice.  So, I wonder if when these stories are taught, that the "moral" of the story is a "given" or is debatable--in Chinese education.  I know how I would treat in in America.
One other question--I think the construction--发充分挥 might trip up many, since the verb 发挥, to bring into play, is split by the "fully."