If you test each cell at 1A, then you but them together of 10p and test the whole pack at 5A, you are then only tested per cell of 500mA. This will equate to a higher capacity of the pack.
To get an equivalent testing, you need to test the pack at the cell tested amp * the cell count. So, if each cell was 1A, and you have 10P, then the pack needs to be tested at 10A. This will get to the closest of the two results. They may be slightly off as slightly lower IR cells will help slightly higher IR.