Wow I can't believe I only just now saw your reply.
Thank you for that! I am actually an intermediate German speaker (I live in Germany), so I understand the principles behind the Der Die Das rules, but I do get a chuckle whenever I bring up a grammatical anomaly to a German and I usually get the reply "Well, that is correct, but it is actually a little more complicated than that...". Happens every time. Maybe next time I'll make one for Den Die Das, just to add to the pile.
But your suggestion is excellent for the beginners. Learners pay attention!