The clone is the one without the scars from when he fell off that grav-bike when they were 18.
If you can grow a clone, you could heal scars as well. Heal the scars of the original, and grow a clone with memories, I think a more accurate word would be replicant. As far as the clone is concerned, he is you, because his memories are exactly the same as yours, he is convinced of it, and if you die, he will do what you would have done if you lived.
Cloning and brain taping is a great way to travel through time.
There is another way to travel through time as well.
1. Find a black hole
2. Build a series of concentric shellworld around the black hole, the black hole is around three Solar masses, from a nearby red giant you feed matter into the black hole, matter accumulates in an accretion disk around the black hole, and about half the rest mass of the in falling matter gets converted into energy.
3. The shellworld absorb the radiation from the black hole and radiate it as heat, a fluid circulates through the radiators running steam generators producing electricity.
4. The electricity powers computers in each concentric shell.
5. The computers simulate 1.5 trillion Earths, each virch simulates a day on Earth going back 5 billion years.
6. Brain tape human beings and grow a clone of each person with memories from the original, this is virch 0. Virch 0 is a simulation of the Earth in the present time, this is the most recent day being simulated.
7. In virch 0 you create a "time machine", this time machine has the capability of going from virch 0 (today) to virch 1 (yesterday) and from virch 1 it can go to virch 2 (the day before) and so on.