In handguns, no, in rifles, yes. Since handguns cannot create hydrostatic shock, differences in energy only really affect potential performance by offering more potential to cause expansion and penetration, but in the end, testing is what finally makes the determination. However, once you get to higher power rounds, energy becomes extremely important. The difference between a .357 Magnum revolver fired round and one from an 18 inch rifle barrel is not comparable, they are of such massive difference that they are in different categories. The rifle doubles the energy, and creates enough to cause hydrostatic shock. Where the revolver will punch a hole in small animals and cement blocks, the rifle will blow them up or crush them.

If you've actually killed things with a .357 Magnum rifle and pistol, you'd understand that huge differences between them. This is what makes the .38/.357 such an interesting case in terms of terminal ballistics; we can go from 150 ft.lbs of energy in snub nosed .38 light loads to 1200 ft.lbs in a hot rifle load, we can see some rounds so weak they cannot deform soft lead hollow points well, all the way to solid nose jacketed soft points having explosive crushing force within tissues.

Its very common to see mistakes from one type of analysis applied to another. This is what caused the huge problem with early wound ballistics research, which assumed temporary cavities in handgun loads was the most important means of stoppage, and this was based on the effects of high power rifles. This, of course, was proven to be wrong, so handgun rounds are only judged by the end bullet, and the crush cavity is based on actual physical crush from the bullet itself. However, the opposite is also true, in terms of people familiar with handgun terminal ballistics only, applying the concept that no shock exists to high power rifles, which is completely wrong in and of itself. High power rounds crush more tissue from permanent stretch cavitation in many cases than what the bullet itself crushes. Anyone who's pulled a pile of mush out of a deer from a .30-06 hit knows this to be true, or watching a gopher explode from being hit with a 25-06. It was wrong to conclude that handguns created permanent stretch cavities; its also wrong to conclude that higher power rounds don't.

So, I will disagree strongly with your assertion, and from first hand experience with these weapons. The longer barrel and higher resultant velocities and energies put the carbine in a completely different category of damage and stopping ability over the handgun.