At 00:19, the aircraft had been airborne for 7 hours and 38 minutes and fuel exhaustion was a distinct possibility. When a fuel tank was depleted, the corresponding engine would ‘flame-out’
https://www.atsb.gov.au/media/566832..._30jul2015.pdf
This suggest that the pilots were unconscious at that time, since one would not wait for complete fuel exhaustion before attempting a perfect ditching on the first try
According to Jean-Paul Troadec, former chairman of the Investigation and Analysis Bureau (BEA), the state of flaperon, even if it is not intact, indicates that there is no violent impact with the surface of the ocean. "If this had been the case with the MH370, one would have expected much smaller debris than this flaperon"
MH 370 : à Balma, l'enquête technique est bouclée - 21/08/2015 - ladepeche.fr
A non violent impact or a "Sully ditching" would imply a calm sea, nose-up attitude between 5 and 10 degrees and low rate of descent. That could only be achieved with the slats and flaps extended. Well, the flaps could be extended only with the engine running and the flaps lever manipulated consciously. With flaps extended, the dihedral angle increases, therefore the aircraft's lateral stability improves considerably, so the aircraft would not get into a spiral dive, even for 7 hours.