To me Parkour, Freerunning, L'art du deplacement, urban gymnastics, obstacle running, rage froobling, etc... are all terms for the same thing. They all describe a vision. A way of life. A way of moving. However you want to express that way, be it an efficient vault or a flashy front flip twist, that's you're personal way of personifying the art. I think names and labels limit us from development and the ability to create new things.
Also, efficiency is dependent on a persons body type, so even if we all were trying to do the fastest and most efficient moves, they would be slightly different for all of us.
Find what's good for you and what makes you happy and call it whatever you want.