"The suits are webbed under the arms and between the legs to slow the fall to earth and give experienced users some ability to maneuver through the air before pulling the parachute."
It works, but not all the time. BASE jumper Mario Richard hits a cliff on the way down and dies. He was 47.
ADDED: Here's video of the kind of human behavior we're talking about:
There's the age-old dream of flying like a bird, but I don't think birds do that, deliberately flying against a cliff, touching it, feeling the thrill of the dare. Watching that video, I thought: These people are consenting to death, if death should reach out and grab them. Thrilling. That's the video they generate, for us... to live vicariously. We're not the ones who die.