Mere Christianity in 8 weeks -- it's not enough time

I've seen notes for Mere Christianity where the whole book was covered in four weeks. I've done a study with one group in which we took one chapter per week (which means it takes almost an entire year to get through the book once you figure in Holidays and other interruptions). I thought we could force the book through at a run in 8 weeks....

It's not working. There is too much good discussion. Too much relevance for each individual, to ram it through in 8 weeks. Now that we're half-way through, it's too late to extend it for another 8 weeks. We've decided to just slow it down and do the part we can do. It was a good experience to try, but I would discourage anyone who leads a discussion-based class like I do from trying it. 16 weeks might be too long, but 8 is definitely not enough.

Maybe if you are a lecturer you could do it in 4 or 6 weeks, but to me the joy is in the discussion.