We can choose not to actually damage the client but they'll still get the you have fallen for xxx damage message. In fact what we do for the safefall AA is just reduce the damage since we're not sure on the effect used yet. You could probably do something like reduce damage based on how much you weigh if you wanted, but since the fall calc is exponential it may be hard to get something that feels right at any height.

Actually, even though fall damage is calculated client side, it can be disabled from the server (at least on SoF). In the newzone structure, we send details of the zone and by setting one of the fields to 1, you will never take fall damage. We had to get this identified and corrected for fall damage to work in SoF. Prior to that, it didn't.