Idk if you've seen one of these dubs/voice overs, but usually the underlying is so quite, it is closer to being muted than actually understandable

Oh this is really cool. I didn’t know that! So foreign films brought to Poland are spoken over with a Polish translator, just like you’d have at the UN? That way you can hear the original actors and the translated dialogue in Polish?

How does this work for trying to learn a new language? I have heard of many people learning English by watching English movies and TV shows with subtitles in their own language. This allows them to listen to English and slowly start to pick up English words while still being able to understand what’s happening due to the subtitles. I myself am learning Chinese and I occasionally watch cooking videos in Chinese with English subtitles and find myself gradually picking up the Chinese words as I hear them.

I think this technique probably works best with shows and movies written for children, as those have much simpler dialogue to begin with.