Yes.. We are agreed with you. We are also facing same issue.
There are different inventory status like ordered, registered and received. Registered inventory becomes the part of physical inventory even process of posting product receipt not fulfill. For posting of product receipt user first need to registered item with specific Serial because we have serialized inventory. After posting of product receipt then inventory status will changed to Received. But we are facing trouble in registered inventory because system becomes registered quantity to the part of inventory and available for sale. System not calculates COGS when sale post of any registered inventory as you better known COGS always calculates after sale posting. COGS calculates on zero amount when sale post of any item which status is registered and also its showing negative inventory impact. when COGS booked on zero amount then its increase the costing amount of item and decreases GP.