UPDATE #2 (added to original post)
Thanks to Famous, there is a way to survive a CJ to max height where you miss the ledge you were aiming to. Basically, what you do is after you realize, that do to a straight up CJ you are going to die when you hit the ground, switch to the gunners rocket launcher. Now, it will take some offline practice to get the timing right but what you need to do is shoot the rocket at a height so when it hits the ground just before you do. It's explosion, though damaging, will slow you down enough to survive the fall. I don't recommend this method except for falls that will kill you. It does do significant damage and should only be used as a final life-saving measure. The best option, would not to do primary CJ's that leave you falling from a great height. Another concusion grenade timed so that it hits the ground and explodes right before you reach it will have a similar fall damage dampening effect. It results in a fun little bounce too at times (though a perfect timing doesnt' bounce you and takes less health ) Both weapons end up doing similar damage. It's really just a matter of which one you can time better. This method can also be used to save your life during falls not as a result of CJ. For example, falling from the cloud platform in XMP-Alcazar, this method, in conjunction with a boost jump can greatly increase your odds of survival.