Payment Method Preferences Validation Logic how does it work?

Summary:

In My Client Groups > Payment Method Preferences there is an option Should the above selected payment methods be excluded from the 100% validation logic - how does this logic work with the Payment amount type "Amount", defined in question prior (refer screenshot below)?

Content (please ensure you mask any confidential information):

The two options we have for Payment Amount Types are Percentage and Amount. We can select to offer Both. The first Payment Method entry reverts to Remaining Pay when additional payment methods are entered even if 100% has been entered by the employee, both will display. Is the validation logic meant to do anything with payment amount type "Amount" or is it designed only to work with Percentage?