I think British people can be ironic even with themselves. This is the cover of a book I found at Pilgrims this year, and I love this kind of humour.
I wonder what our students would think about it and if they would understand it. Sometimes jokes are the most difficult thing to understand for a beginner, or even a student at elementary level.
Or maybe it's not a question of level, but of how you lear a language. Would you learn something about the culture behind the pure grammar and vocabulary? If your answe is yes, you have good possibilities to understand humour and irony.
Otherwise, all you get are just words.
:-D