It's Hotrod180's fault. He lured me into Wolfgang's explanation of zoom reserve on page 53 in "Stick and Rudder." In the middle of the night I realized why I so dislike Vy and V speeds in general. Best rate of climb seems to discount a better gut feeling on takeoff or during low level operations: Zoom Reserve.
Vy is the (very limited thinking) most up over time for a given engine power setting in stable air. It totally disregards ground effect energy, thermal energy, and wind energy including orograraphic lift.
Vzr, Velocity zoom reserve is a bester rate of confidence. It makes me feel better anyway.
MTV has pointed out the need for Vx in the exact shortest field before obstruction situation, and he and the POH are right. Wait! Did the POH take low ground effect into account? What about getting into low ground effect quickly with flaps and/or dynamic proactive elevator control. I can go along with Vcbbx or Velocity conservative best book angle of climb.