I agree Bohemian. I believe in WW's death she would of either been knocked unconscious or dead as soon as her body hit the first solid object, and would not been aware of hitting the ground below.
My son died a violent death in an MVA, and the autopsy report showed multiple injuries, compound fracture of his femur, lots of internal bleeding, bleeding around the brain etc. etc. But i knew that he was already gone as soon as impact happened and wouldn't of known much about it. Our bodies are geared for death, we all die somehow eventually.
The thought that i had too was when i have ever badly injured myself like nearly cut off a finger with a sharp knife while peeling veggies, i didn't feel it straightaway, and once after a few seconds we do that's when the pain sets in.
But anyway autopsy reports are after the fact and even though they sound awful and as you say it's only us left behind that grieve.