Of course it makes sense. This is the modern geomantic theory. In ancient times, there were only small bronze mirrors, which could be moved and placed anywhere at will. At that time, there was no glass mirror as big as it is now, but if you are used to the shadow in the glass mirror, it is not much problem to look at the mirror day and night. For a small room or room, you can't get a small mirror like the ancients or the poor years of previous years. The mirror in the bathroom is outside the bedroom and has no effect on the bathroom. If you must pay attention, you can add a curtain to the mirror and open it when you use it. But after a long time, the curtains are probably too lazy to pull.
For reference.