Sorry for the quick english translation, I used Google to translate my comment from a french web site (http://www.ultimateps3.fr/forums/message-662207.html#p662207). A.K.A.: lordsith because I am in a rush right now and I want to share my tought with you as soon as possible so sorry but it is readable.:
told you it'll play told the story of Frank Jaeger (Gray Fox) and how
he became a cyborg after the incident in Zanzibar (Zanzibar Land
Disturbance) or he was forced to betray his best friends: Solid Snake Because of this loyalty to Big Boss.
It appears for the first time in the game Metal Gear (1987) and subsequently in Metal Gear 2: Solid Snake (1990) Metal Gear Solid (1998) Metal Gear Solid: Portable Ops (2006).
Frank Jaeger, born in the mid-1950s, is the son of an American soldier and a Vietnamese. Rejected by all, he has participated as a child to a conflict in Mozambique. The boy approached the enemy, who were wary not a child, then he attacked with a machete and slaughtering his enemies. Because of this approach, and the fact that he spoke a little German, the boy was nicknamed Frank Jaeger (hunter franc literally). It was during this period he was spotted for the first time by Big Boss. This put him in an orphanage, but it was taken, apparently by philosophers, for submission to the program "perfect soldier".
After the incident in San Hieronymo, the sole survivor of this program, Frank received the code name Null. Conditioned to lose all memory after completing his mission, he is nevertheless marked by his fight against Big Boss. It also recognizes the young child soldier in Mozambique. After a second battle against Big Boss, Null found the memory and Big Boss takes him under his wing. At the end of Metal Gear Solid: Portable Ops, Roy Campbell explains that although alive, young Frank is still traumatized physically and psychologically, and he will [b] stay in a hospital [/ b].
Jaeger is the only unit FOXHOUND soldier to reach the rank of "Fox", the highest distinction of the unit, and was decorated five times.
Later, after Snake had discovered the plot Drago Pettrovich Madnar, Gray Fox launches an attack against the commands Snake Metal Gear. This last is destroyed by Snake, but Gray Fox is still alive, and a fistfight in a mine field begins between Snake and Gray Fox. Solid Snake wins the fight and left, believing him dead.
Gray Fox did not survive, but her body is recovered and returned to the medical officer of Fox Hound, Dr. Clark (aka Para-Medic) who used him as a guinea pig for gene therapy experiments. Gray Fox was raised and grafted exoskeleton experimental sees him will increase his strength and agility, but also its discretion with a new optical camouflage technology.
In 2003, the adoptive sister of Gray Fox, under the alias of Naomi Hunter enters the unit Fox Hound, using camouflage to escape and the murder of Dr. Clark commits that Gray Fox in his laboratory .
So phantom pain, VR Therapy,'d go with this scenario and Kojima himself has said repeatedly will tell this part of the history of FOXHOUND. Especially in the trailer for The Phantom Pain VGA 2012 if you are careful frame by frame you can see the character's face looks like a Snake back but when you see his face is me for sure. Over a several places in this trailer you can see Big Boss sketch on the walls (among others) made by the artist Yoji Shinkawa.
I really think putting the point on this mystery I know if I'm wrong, well, it would be a shame because everything is in place for this story."