While the whole article is worth a read, I think he's beutifully breaking some new ground/calling out the elephant in the room when he gets into the numbers and economics of it all.
His hesitation to tread into such traditionally market-seeped and potentially divisive territory is certainly to be applauded; but the real prize is the golden questions he poses when he actually does get into it!
You can read his whole post here, or just nibble on my favorite part below.
(For context, the post is in response to comments made by Mark Driscoll suggesting that missional communities don't have any converts.)
"I think that the missional communities that do persist may have a higher conversion rate than the Drsicollesque mega church. Missional churches are so much smaller. 6 conversions from a group of 25 over ten years would match (or exceed) the percentage growth of a typical mega church. I think it would be interesting to measure how much dollars per conversion are spent in missional churches versus mega churches five to ten years from now when conversions start manifesting themselves in missional churches. I know I am not supposed to think this way, but I still smile when I think that indeed missional churches could be more cost effective when it comes to conversions because we resist spending money on buildings, programs and the show."