Yahtzee did not say parkour cannot work, just that they could not be bothered to make it work in this game. It is a matter of perspective, and first-person does not give enough dimension to accomplish this. When you do not have an innate sense of how tall your character is vs the distance to jump vs the size of the platform to land on, you tend to miss more than you should if you have all those wonderful parkour-fu skills. I hate to say this, but for once they just need to remove the player-based skill and automate the system. Move to ledge, check for skill level, wait for button press, and either perform maneuver or tell player they are not quite ready to commit suicide in that manner.
+1 for Jet packs or wingsuits (+2 for both).