RE: Who said that physics wasn't fun?
In response to the original statement
"However, all things being equal, two projectiles, one with a greater mass strike a target with the same velocity. The lighter projectile will almost certainly have a greater KE ...."
By formula this is not correct. m=mass=w/g which is the only variable in this statement since the velocities are equal and acceleration do to gravity "g" is constant (location of the test is the same location on earth). If you work out the solution (by the equation for KE) for different arrow masses but same velocity you will see that the heaver (more massive) arrow has more KE. Byassuming same velocity for both arrows and the same instance in time it is implied that there are no losses (drag, heat loss, etc.)