The reporting UIs do not include the line item "Inside your Site". So the report is not taking into account visits that start with an internal referrer (session refresh). Data Warehouse will show this additional referrer type. Feel free to run a Data Warehouse and compare.
I suspect that the different in totals (Sum of UV being more that total and sum of Visits being less) is due to de-duplication. A Data Warehouse remind may confirm this as well.