Sprouted Struan Bread (Reinhart's Bread Revolution)

The Sprouted Struan Bread in Reinhart's Bread Revolution provides for a whopping 2.9% instant yeast (baker's percentage). Could this be a mistake? The recipe in the book calls for 5 teaspoons (!!!) of instant yeast for 522g of flour. The formula is as follows:

Sprouted whole wheat flour: 87%

Sprouted corn flour/cornmeal: 8.7%

Sprouted brown rice flour: 8.7%

Salt: 2.9%

Instant yeast: 2.9%

Brown sugar: 16%

Water: 54%

Buttermilk: 33%

Cooked brown rice: 11%

Any insight would be greatly appreciated.