Before revision:  The equation is general in the sense , that it does not depend on the terminal utility , and provides additional analytical insight for some optimal investment problems with known solution. Furthermore when boundary conditions for the optimal strategy can be established independently, it is considerably simpler than the HJB to solve numerically.
After revision:  The equation is general in the sense , that it does not depend on the terminal utility , and provides additional analytical insight for some optimal investment problems with known solutions. Furthermore, when boundary conditions for the optimal strategy can be established independently, it is considerably simpler than the HJB to solve numerically.