Boiler external weather sensor + tado
It would be nice for tado to use the boiler external weather sensor if installed while running on opentherm/bus for more accurate heating.
Well, weather stations are not all over the place and not so accurate in some zones, so it would help people in remote locations.
Tado 'weather compensation' is little more than a gimmick. As you say, it's largely inaccurate.
In your case, as you have an external sensor, you have a weather comp boiler, but by wiring in to OT, you're overriding the weather comp and using tado load comp (OT), as they're either/or control technologies - one sets flow temp based on weather and the other on internal demand (although you can have WC with internal feedback as part of the WC).
Usually, properly set up WC performs better than LC, but you need to wire in on relay to prevent OT override.0