MaxScript - true uvw planar fit

Does anyone know why, when pressing 'fit' in the uvw mapping modifier does the size of the gizmo not equal the size of the object, buts actually equals the size of the object plus the size of the object divded by 1,000.

should be... uvw gizmo size = object size,

But Max does... uvw map gizmo size = object size + (object size / 1000)

... just curious as im doing some max scritp around this