Espn did an article that didnt get much publicicty because Espn lives off sports. They found test results from individual teams, which arent required to report to MLB, that 3 out of 5 players from spring training each year test pos for gear.
Look at Sosa, He is huge in the spring. Throught the course of the year, loses some size.
Look at Big Mac as a rookie, he has put on some 40lbs of solid muscle. ANDRO?? No way!