Thanks, everyone. There's three layers to this
a) what we believe needs to be checked
b) what is the present sentence saying, rightly or wrongly
c) what Airbus engineers and system designers want us to do.
We seem to share the belief that the pressure at the pick-up point is what's relevant, and looking elsewhere is not meaningful (A).
The crux of my post was to get a precise understanding of B), in order to confirm or re-discover C).
Wwhat does the sentence say, to the naked eye, without preconceptions? Which side [receiving/supplying] would you pick if you had to demonstrate
following the sentence itself as-is, and the punishment was transferring to Boeing fleet?
Playing the devil's advocate for the semantics of "supplying side" (B), and Airbus actually wanting us to do exactly that (C) yields some nice findings, t.b.h.
- there's hearsay that dropping below 30 / 25 does not create any practical issues
- the 737 guys (same engine) only have one manometer (duct pressure) with the sensor somewhere in the middle
- for H.F. it is an easier read, a less demanding cognitive task
- if we are dumbing down the cockpit procedures, or as some might say "tech evolves to meet the operator", this is not foul play on the SOP part if properly vetted from Airbus / CFM.