Speaking of difficulty... I am impressed at how difficult giving
somebody credit appears to be, here on UseNet. Calling someone a
"coward" is not uncommon, even though it's silly.

Let me try to illustrate the intended point another way. The stunt
starts about here.

http://www.youtube.com/watch?feature...VRJowk#t=80 s

Jeb Corliss is not just flying over terrain that is declining at
least as fast as his descent rate. What appears to me to be the
very difficult part is that he flies within 10 feet of the ground.
If that's not exceptionally difficult, you should be able to point
me to another video of someone else doing the same thing (or
similar, at some other location). What appears to me to be
unusually difficult about his stunt is that he has no escape
route. Some wingsuit users fly close mountain sides, but they can
abort simply by steering in the opposite direction at any time up
until the last second.