Can anyone clarify the following section from p469 of the ref guide?  It seems to be saying only include MEP materials that are credit compliant in calculations.

However, unlike furniture, if some of these products are included in credit calculations, not all products of that type must be included. For example, if the cost of ducts is included in the MR calculations for recycled content, the cost of ducts that do not meet the credit requirement does not need to be included in the numerator or denominator of the credit calculation. However, the denominator for cost-based credits (all Building Product Disclosure and Optimization
credits) calculations must be the same.