Svarin, thanks for your inputs. I was thinking that the ADR1 / FCPC2 wiring failure could have been just a transient. I find it is unclear how exactly pitch control works in ALT1 / ALT2. Whilst these reconfiguration laws can be triggered by 2 or 3 unreliable airspeed sources the FCOM says it uses speed. I offered that the FCPCs may use a “default” speed value or default gains in case of missing (or unreliable) airspeed data. Good enough for me.
My point is: an FCPC in charge of pitch control in a load factor demand law, which is the case in both ALT laws, apparently have to establish, one way or another, reasonable gain values. Now what happens if in a particular sequence of events, especially when the ADR data may be restored randomly and asynchronously relative to the computer’s sampling rate, this FCPC is led to use (perhaps momentarily) an erroneous speed value and then determine wrong gains? Is the airplane always flyable in such a case?
Of course I have no doubt that all the software was carefully studied and checked in all possible ways but sh*t happens. I agree this may be far-fetched and stand ready to be guillotined.