You see people say this a lot with goldfish, the problem with fish is that the body stunts but nothing "stops growing" so the internal organs will continue to grow until they rupture the animal. Its very painful and slow, not to mention down right cruel.
The same idea applys to dragons they dont stop growing they just kind of slow down. I rescued my lil guy from someone they wasnt feeding him and wasnt regulating his enclosure properly. After the right care he grew 4" in about 5-6 months and at this point he was already almost 2 years old. (Which should have already been full grown) Stunting MAY occur but it is stressful on the animal and may cause death, or other harmful health concerns.