A great Don moment was at the SMBC Preachers' Conference a few years ago, when he was illustrating the problem of biblical illiteracy (I quote loosely):
And it's not just lay people. I was at a pastors' conference and mentioned Jotham's fable. And they didn't know what I was talking about! Let alone what the difference between a fable and a parable was...
And we were all nodding our heads and tutt-tutting... while casually skimming through our Bibles trying to find Jotham and whispering to one another about what the heck was unique about a fable.