Connection between ITRS and bond prices

11th hour states that "if the price of a risk-free bond is less than the investors ITRS, then they would purchase more of the bond. This increase of investment leads to a decline in current consumption, which brings an increase in MUc and a decrease in MUf. Consequently, the ITRS falls until it equals the price of the bond"

I dont understand this. If ITRS is falling, it means times are good. Which means rates should be rising. But how would rates be rising if bond prices are being pushed up by investors that continue to buy them?