My TTN experience is that the TTN core sends downlinks with ADR commands in Frame Header FOpts when a device has set the FCtrl.ADRACKReq bit = 1 in an uplink Frame Header.
This is covered in section 4.3.1.1 of the LoRaWAN specification (v1.0.2). Section 2.1.9 of the LoRaWAN Regional Parameters (again v1.0.2) for the EU states that FCtrl.ADRACKReq should only be set once every 64 uplinks.
So… ADR will normally only operate once in every 64 uplinks. If you have a device that defaults to SF11 and is sending updates at the 1% duty cycle limit then ADR will only operate once every approx. 100 minutes.
This is simply way too slow for a “mobile” device and will result in a lot of lost uplinks if the FCtrl.ADRACKReq uplink is sent during good cover, the device is switched to SF7 and reduced TX power and then moves into poor cover.
So… the guidance is correct… ADR is very relevant to static devices but should not be used for mobile devices.
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