the first time you see a quad with no use of his lower legs go from floor to chair, trust me you're like "whoa" and then you sort of get used to it.i have a friend with one full limb (a leg) who drives an unconverted car, works a full time job and does fiddly stuff all the time with no hands whatsoever. when you don't know and don't have experience (and i was the same before i did) it just never occurs that they can do these things like everyone else.
And actually Zupan dives straight out of his chair and into the water, he can life his own body weight no problems