When do I use Header Only Test Sequences+ and when do I use Header Plus Test Sequences?

When do I use Header Only Test Sequences+ and when do I use Header Plus Test Sequences?

Header Only Test Sequences are used when it is assumed that the measured values for gain, level, cropping, and shift are constant over the entire time-invariant test sequence while making signal quality measurements. When using Header Plus Test Sequences the measured values for gain, level, cropping, and shift in each field is used in the preprocessing when making signal quality measurements.