From the abstract:
Lastly, a theory that the opisthotonic posture of fossils such as Sinosauropteryx NIGP 127587 occurred perimortem as a consequence of neural spasms provides the basis for a forensic reconstruction of the stages leading to the dinosaur’s death and the final preserved position of the external, dorsally preserved soft tissue, which proves to be more consistent with a uniform crest than individual, free protofeathers.
Too bad that the hypothesis of perimortal spasms has turned out to be quite unparsimonious. I was there at this year's SVP meeting when a video showed what happens when a dead chicken is put in water: the intervertebral ligaments contract, the dorsal ones are bigger than the ventral ones, and _within 5 seconds_ the top of the head touches the back.
But back to the topic. Uniform crest? Then why are stage I feathers preserved elsewhere on the body?