Sunchips specifies 14 weeks in a hot and active compost. A new compost pile (like in the experiment) would not be very active compared to an old one, especially since he didn't add any worms to it but he did get the water and turning right. He also mentions that it was cold and rainy in the weeks after he started his compost. An old compost would shrug this off but it would have a negative effect on a newly started compost.