It was explained to me by a coach, using level 4 vault as an example. When you are looking at a 5 ft girl vault vs one that is just 4 ft, minor form breaks, like a slightly piked body, bent knee, will be more pronounced on a longer body. Longer legs will will make a slightly bent knee more obvious. On the same topic, a taller child will need more strength to get that extra foot of height, tight, then someone a foot shorter. From a judging perpective, sometimes those smaller foam breaks are harder to see on a smaller body.
My DD is young, when she started level 4 at just turned 7, she was already 6 inches taller then any other child on the team her age. Actually, when she would stand on the podium in 2nd or 3rd place, often her head was the same height at the girl standing in first. So regardless of the age, the height is something we have always dealt with. She also looks and acts 2 yrs older than her peers. I never felt she was judged unfairly. But I have seen smaller girls with big bows and smiles, get much higher scores, sometimes higher than deserved.
In my state there is a bias in judging, but has nothing to do with size and age. I could go on, but I won't.
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