SL
There are frequent exceptions to the containment of an address within a boundary. E.g. take a house that is built at the outskirts of a town. Formally it might stand in the adjacent district, a few meters beyond the boundary, but often it will use the same postal street/city address than the houses it is next to, for convenience. OSM is proud to show such exceptions, based on ground verification. Calculating some address components from the boundary relation will produce wrong results.
Я ровно об этом спрашивал в теме на форуме - не может ли быть ситуации, что адрес на самом деле не тот, что вытекает из границ?