My coach always want me to throw 50 BP balls, he thinks i’ll get control if i do it.
Both of my coaches, who played at the college and pro level, are big advocates for throwing BP. I could definitely see how it would help you learn to throw to spots.
Face as many live batters as possible, but I would not just be up there wasting throws for the batter’s enjoyment, unless I’m just getting loose because I had thrown the day before in a game or bullpen. If not the above situation, this would be a BP where I’m trying to make them look bad and they are trying to learn how to select good pitches to drive or to hit in situations.