i have raised many ST;s from one inch size to around 15 inches, their necklace usually splits from the bottom and from asymmetrical from a young age to symmetrical at an older age and vice versa. it is very hard to predict as food size of tank or pond and exercise from fishes that it lives with can affect its growth; vertically and horizontally.
but the competition ST widebar bar in Thailand is short and thick, with full necklace and the most widest middle bar, which the rest of the bars on both sides must be straight with no dents or curves and must look smooth to the eye.
just to let you know.