This method has a Customer object and a ProductAttibuteValue object as parameters.
It performs a test on the ProductAttributeValue.AttributeValueType
If Simple, it performs some calculations but uses GetFinalPrice with the Customer object parameter
However, if AssociatedToProduct, it doesn't use the Customer parameter, it uses _workingContext.CurrentCustomer in the call to GetFinalPrice
This seems inconsistent - surely, the Customer object should be used in both cases?