On the other hand, if your assertions are correct, I might be home free on the zone-level control providing I can find the needed wire pair without having to physically wire the sensor (which would be quite difficult as it is on the far side of multiple large concrete expanses). This may work in some circumstances, but where the user is away from the property and has multiple zones the only options left to them are to allow all zones to keep running or to shut off all zones-thus risking or killing their landscape. There is nothing about zones being skipped or not skipped, nor about calibration, only about absolute gallons being measured. Your statement stands in contrast to what I saw here in the Help Center.
It failed to state categorically that a leaking zone would be skipped, but inferentially the statement was adequate.
The now-discontinued setup of a Wireless Flow Sensor calibrated each zone and said comparisons between calibrated values and measured ones were used to ensure “good zones” were not skipped when a leak was noted. From the 'More' tab, select 'Accessories,' then add the Rachio Wireless Flow Meter.
Do not put the batteries in the Wireless Flow Meter until prompted. I do not have one setup as such, but when going through the process of adding a flow sensor to a Gen 2 controller, similar calibration prompts show up as if Gen 3 was used… (em added) Take the Wireless Flow Meter to the backflow preventer where it will be installed.