Restriction
I think we may be going in the same direction. Additionally, it might be more harmful than not to be so focussed on precision in FADEC. I think the system probably worked perfectly so I use it only to suggest that in ETOPS it may actually be helpful to introduce anomalies of benign nature into the control system. If a Fuel source is Homogeneous, sourcing it in different locations in the A/C creates a tolerable "discontinuity" that may introduce a higher level of safety, rather than a lower, albeit predictable, one.
The authority I would suggest, Daniel Bernoulli, dead, but his work lives on.