“Chest development” referring to hypertrophy or growth, being the goal. So not really unspecific. And that logic wouldn’t entirely follow.. for example benching or db benching will grow your chest more than flys will.. take another muscle group like back and bi’s, rowing isn’t going to hit your biceps as good as a bicep curl, so in that case you couldn’t apply it to *any* isolation exercise in reference to growth. Some muscles grow better isolated, others not so much