#1
The AAIB have already said both engines failed to respond. That has come from hard data, not human perception.
#2
We don't know that for a fact. That part of the report could well have come from the interviews with the Pilots.
Yes we DO know. That info comes straight from the AAIB's site.
"the Autothrottle demanded an increase in thrust from the two engines but the engines did not respond."
http://www.aaib.dft.gov.uk/latest_ne...ial_report.cfm
Please check your sources.