Right now, the treatment planner is still calculating based on an old Traditional method of COB, which almost nobody uses anymore because it resulted in patients getting money back instead of ever paying anything out of pocket...false credits.
Standard secondary coordination of benefits calculates based on what's left after the primary pays. If the fee is $100 and primary pays 50%, they pay $50. If secondary pays 50%, they pay 50% of what's left...so they pay $25. There is more than one...