Whilst IFTTT can trigger on temperature thresholds it is not aware of the scheduling and heat request status. There's definitely scope for an Excess Temperature Detection feature that would alert when a zone becomes too hot, too cold or simply fails to heat when the heating is scheduled on. I'd find this more useful than the Open Window Detection.
Excess temperature detection can now indeed be programmed only in IFTTT with the set temperatures hardcoded in the temperature checking script. It would be very useful to have a trigger "Temperature in <valve or thermostat location> <X> degrees <higher/lower> than set temperature". Some aspects to be taken into account are verandas with sunshine (although tado knows this by its weather function) and people adding heat with electrical systems. Both however will trigger still expectedly and could have useful trigger actions.
I have a bug as described:
whereby the tado system triggers the Junkers boiler to go full on without any programmed reason. In that case, I had expected the Care&Protect function to kick in, but it finds this all ok.