The concept of a bullet dumping energy is a logical one, makes for interesting energy dissipation theory discussion, and by itself has no bearing on hunting effectiveness.
Stating a minimum energy number to kill a game animal under hunting conditions assumes the hunter understands the concept of proper hunting bullets, and has chosen the correct bullet for the application.
Energy on it's own is not a criteria.
Energy is dissipated in many ways.
The way the energy is dissipated depends on the bullet construction, impact velocity and shot placement.
A bullet can "dump" all it's energy on the animal, and the animal keeps walking for weeks with an ugly surface wound for next year's hunter to find it's skull somewhere.
What all hunters should strive for, is a quick kill under all conditions, not an energy number.
This is by using a properly constructed hunting bullet at the right velocity, that is certain to kill quickly with proper shot placement.
That is a whole science, matching bullet types to game type, correct placement and velocity at any given range for a clean kill. The energy number is a by-product of the result, not a pre-condition.
Don't justify how you hunt by how much energy your bullet carries on paper. Rather state your bullet type, and the velocity it's at when it reaches the target - and then add the energy number to the end of the statement. That is all implied when energy numbers are used in the context of harvesting game.
That is why the minimum velocity for expansion of the correct bullet type needs to be known. You make sure it reaches the target going faster than that.
The energy number is never predicted, it always follows observed effect.