I think he does stage a lot of his show, but thats not to say he doesnt still do some pretty crazy stuff like jumping into frozen lakes to demonstrate a technique in how to get out, or climbing up sheer rock faces with no ropes, abseiling down into crevasses and climbing out, skinning and gutting a camel then getting inside ...
apparently what he 'fakes' is sleeping rough and instead stays in hotels after a days filming, which to me doesn't take away from the fact this guy is fairly dedicated to showing survival techniques, granted he'll be getting paid a mint for it.
He was in the SAS before, which i think on its own shows he's pretty hardcore, but broke his back when a parachutte jump went wrong, then after recovering became Britain's youngest person to climb everest i believe it was.