Suppose the new system delivers more detailed information than the production system. This means that the number of lines in the two files does not match and you cannot get an exact match. But you still want to know if on the level of detail of the production system the new system delivers the same information.

With Spirit you can group the detailed attributes of the new system to the higher attribute level of the production system. This does not mean that you can find out if the new system splits the information the right way, but you can at least find out if the aggregated information is equal to the production environment.