That's funny. Perhaps physical maturation rates are not measured with the star system. There is not a person in the medical profession that does not know that male physical development to maturity spans a longer period of years than females. Furthermore, all the weight lifting in the world for many young athletes will not add body mass at 17-18 years old as when they are 19 and 20 years old. You are right about serveral things. Barkley was ranked a 4 star based at the end of his senior season and that was about right. Look at his weight and physique at that point. Look at Barkley after he dropped track from his sights and focused solely and with great seriousness on building muscle mass for football.
The point is that these snapshot ratings are cute gimmicks to grab our attention and make us pay for 'insider'... lol.... information which ignores very significant inside information. An old guy that developed what he called the 'bird dogging system of rating HS talent' made us oldtimers involved fill charts with freshman, sophomore, Junior and senior ht, wght and various speed data while filming players and factored these into decisions. Now they through a 3 or 4 star on a guy and say he has a huge upside.... or some such phrase. Stars are nice things.... and then there are Nassibs. If your program understands and lets it happen.