The case study you included at the end was the "aha!" moment for me. Seeing the actual graph of the growth trajectory makes the theory much more believable. Was that growth purely organic, or did you supplement it with a social push?
Great write-up, though I have a slightly different perspective on point #4. In my testing, I found that the alternative method yielded faster results, though perhaps less sustainable. Have you compared the two directly in a split test?