Kinda disappointed the total emphasis is on him being a "hell of a good pilot" instead of the control engineers who allowed the plane to compensate for losing a wing. There's no way that plane would have stayed in the air without their work.
In the case of many of the incidents reported here, the scenarios have been recreated in flight simulators. In the case of UA-232 in particular, I don't believe any of the simulator pilots managed to exceed the performance of Alfred Haynes.
The official NTSB report is opaque on this but suggests simulator results weren't encouraging as far as training to avoid this type of accident:
The DC-10 simulator used in the study was programmed with the aerodynamic characteristics of the accident airplane that were validated by comparison with the actual flight recorder data. DC-10 rated pilots, consisting of line captains, training clerk airmen, and production test pilots were then asked to fly the accident airplane profile Their comments, observations, and performance were recorded and analyzed....
Overall, the results of this study showed that such a maneuver involved many unknown variables and was not trainable, and the degree of controllability during the approach and landing rendered a simulator training exercise virtually impossible.
That said, I imagine being controllable while missing a wing was a side effect of the performance goals addressed with the fuselage's lift, or the design goals addressed with the width of fuselage relative to the wingspan. Flightworthiness without a wing probably was not a goal, though we can assume that many features such as the one-way fuel valves that make it able to sustain inflicted damage were very important to its survivability in this case.
It sounds like the pilot adapted his tools and equipment, and successfully used them in a situation they were not designed for. If you develop some innovative software, it may not have worked without the specific compiler you used, but that isn't the same as saying the person who wrote the compiler wrote your software. It is difficult to tell from the story whether landing was something that very pilots could have done, or whether it was a more or less natural response to the feedback he was getting from the aircraft in the cockpit.