Jim .... dV/dt is not the same as V/t.
Acceleration is dV/dt ... the "change" in velocity with respect to time.
In other words ... it's possible for "person-A" to have a lower velocity at impact than "person-B", yet for "person-A" to have greater acceleration than "person-B".
This is why it is important to 'throw' and allow an unhinging type action. This is why a forced palm-up extension is not such a great idea.