From the BBC:
However, as he made the flare manoeuvre - a stage of the landing shortly before touchdown - "his prosthetic limb became detached from the yoke clamp, depriving him of control of the aircraft".
While he had thought about getting his co-pilot to take control, the time available and the challenging conditions meant his best course of action was to move his right hand from the power levers on to the yoke to regain control.
"He did this, but with power still applied and possibly a gust affecting the aircraft, a normal touchdown was followed by a bounce, from which the aircraft landed heavily," the report found.
The AAIB reported that the captain had said that in future he would be more cautious about checking the attachment on his prosthesis as he may have dislodged the latching mechanism.
He also said he would brief his co-pilots about the possibility of a similar event and that they should be ready to take control at any time.
Para 3: "a gust affecting the aircraft" could happen to any of us BUT, if he'd had a hand on the throttles he could have adjusted power.
Sorry, but I do not wish to be flown by someone with bits missing. There's enough which can go wrong without deliberately starting off with a built-in disadvantage.