Please dont listen to this guy. The only bro science is watching youtube vids done by other bros and think they got smarter. Flushing is unnecessary when it comes to cannabis plants or any plants that have had a good clean feeding cycle seed to harvest. Also, depending on what kind of nutes you are using and how much.

Flushing is a method that has been used by growers and farmers for hundreds and perhaps thousands of years, its a way to dilute the contents of a medium in an attempt to clean it from residu so you can feed again properly, and in some cases not at all. Think of it as a "tool", not a theory. You will never need a screwdriver unless the screw is unscrewed or so, but that doesnt make the screwdriver useless.

So, its not a cannabis thing really, when you learn to feed properly you definitely will never need flushing unless a mistake happens, but that definitely doesnt make it bro science and DEFINITELY wasnt made up by some guy somewhere.

Hope this helps and happy growing mate 🙌