Photography Corner provides this concise article on better b&w images.

Basic B&W – The Next Step | “Everywhere you look, you see suggestions of using saturation rather than the remove color option available in Photoshop. It’s supposed to be better. What they don’t tell you, is specifically WHY it’s better. Well, if you use layers, then it’s being done in a none destructive way. But that’s it! That’s all the benefits wrapped into one. And once you convert you have the exact same picture. Desaturation is after all: removing color.”