US Emissions to Stay Below Pre-Recession Peak Until 2028

Here's an interesting chart from the recent National Academy of Sciences report America's Climate Choices. It projects that [energy-related] US CO2 emissions won't rise back to pre-recession levels until 2028, assuming business-as-usual, as a result of better energy efficiency and lower economic activity in their recession:

Lester Brown thinks US emissions are headed for a massive decline. I am skeptical.