Yet another idea!
The latest AAIB report has indeed focussed our understanding and has allowed different weighting to be applied to different potential scenarios.
Now the significant new bit of data (IMHO) is the similarity of the actual EPR at WOT (wide open throttle).
What could cause such similar limiting EPR on BOTH engine installations?
I believe we have to be talking of shortcoming in either Design Concept or more likely Standards. i.e. everything was within the agreed operating parameters which is why nothing untoward can be found.
I therefore make the following contention.
As fuel temp decreases its propensity to wax increases but this transition (I believe) is not clear cut being dependent upon the degree of molecular disturbance/agitation.
Now the fuel must have been flowing adequately to maintain cruise requirements which I assume would have been similar to that demanded during the ill fated finals.
However during the descent the reduced fuel demand at flight idle MAY have allowed already very cold fuel to transition to wax due to reduced molecular agitation.
This would fit with the indication from the AAIB that (low temperature?) flow testing is being undertaken.
In addition I have always been "suspicious" about the fuel.
Its wax point has been verified at -57C, a full 10 degrees better than specification. I keep asking. Why?
So maybe the fuel was within specification but does anybody have any idea how this test is conducted (i.e. Is the fuel placed (statically) in a vessel in a lab freezer or is the fuel agitated in someway during the test?)
I also remain surprised that no directive has been issued requiring a temporary tightening of minimum fuel temperature permissible.
I look forward to your response and further debate.