Before revision:  The DMRD condition implies log-concavity of the expected profits per unit of output without additional assumptions on the existence or the shape of the density of the demand intercept and  hence, answers in the affirmative the conjecture of Lagerl\"of (2006) that such conditions may not be necessary.
After revision:  The DMRD condition implies log-concavity of the expected profits per unit of output without additional assumptions on the existence or the shape of the density of the demand intercept and , hence, answers in the affirmative the conjecture of Lagerl\"of (2006) that such conditions may not be necessary.