Back in the day (90s or mid 2000s) I remember reading about some builders saying that with certain steroids they would inject in certain muscles to spot grow them slightly ahead of other muscles. I don't read that anywhere lately, is it because newer studies have found it doesn't work, or is it only a very limited amount of substances which will do this? (I.m fairly sure they weren't talking about those temporary muscle inflaming injections but might be wrong)