Using Headcount Values in Reports and Dashboards

Content

I am trying to use headcount values in reports and dashboards, but the values are not lining up correctly.  I know how to load the assignment work measure via HDL, so correcting some of these issues is possible.  My question is more of a best practice. 

Oracle documents defines headcount as:  A work measure recorded on an assignment. By default, the headcount of an organization is the total of primary assignments in primary work relationships.

I also noticed that if you have an employee with multiple assignments and you change the primary flag, the system does not automatically change the headcount value (removing the value from the non-primary and adding it to the new primary).