That's how I prefer to interpret flushing. I wouldn't call it bro-science either as I've used this technique to save a nute-locked plant.
Leeching is a better word to use for when you let the plant use the rest of the available nutrients in the medium, but this is more for salts. I also do this to save some money on nutes, but you either want to have a good eye to predict mature-ness, or know the cultivar timeline. For organics, depending on the nutes, it may take a while for the top dress to be broken down by the microbes to make them plant-available. So what you add today might not be plant-available until 1-2 weeks from now.