I also look at it this way.Supplements have been part and parcel of the codes for ages.Administered by one assumes the conditioners/trainers,with the supposed knowledge of the doctors.
Injections would be a concern, I would suggest for an individual and or a team ,a change in supplements by oral use under the above conditions would be of a less concern for a fooballer ,as this is a team sport and not an individual one like cycling.
The ASADA code where supplements are legal then become illegal ,and grey areas in between,how in God's name is a footballer supposed to b an investigative detective.they make it seem so flipping simple.
The testing bodies should have come out some time ago ,and spelt out in bllack and white what is and what isn't,instead of these are legal and the remainder are not.Spell out the remainder in detail,not generalise.