Not that have experience, but I feel like that's just practice. Your subconscious needs to learn that it's not necessarily going to die when it does that, and your subconscious learns from experience, so if you did it 10 times and nothing went wrong, you'll be less scared.
I experienced this with skiing, where [1] you need to look down the hill and lean forward amongst other things for best results, things your fear reflexes want to avoid at all costs at first.
But with the parkour on top of city buildings that is more extreme than what they portray on rooftop chases in a Bourne Identity movie... hmm... I think that is another level. There is a good chance you will die if you do that alot over 10 years. It probably requires some letting go of ego to the point where you are happy to die early. Like the free and solo climbers.
[1] Forgive me if you are a great skiier this is my dumb interpretation!
Skiing is a unique sport in this regard, different to snowboarding in the way one needs to stand.
With Skiing, you have to make yourself quite vulnerable. It’s instinctual for us to want to close ourselves up to protect our organs when scared. But you can’t ski well or difficult terrain without opening your body up, relax your arms and expose your vulnerability. This is especially scary at first when tree skiing. When you do relax it’s amazing.
I think this is why some like snowboarding more. You’re facing sideways and you feel less exposed. You can get away with being closed up a little more and while it’s bad form, you never really have to snap out of it the way way you do on Skis.
I think without fear, challenges to over come, ways to improve, there would be little point to living. Experience would be so bland?
The feeling over fear when you want to ask someone out, then you do it and it works out, that is the spice of experience. Like wise when it doesn’t work out, it can suck but it’s also part of the spice.