TRICARE works together to attribute costs with M4A – no reason that the plan uniquely kills current practices
US Coast Guard, ND, Sea Legs - Health Care, https://www.dcms.uscg.mil/Our-Organization/Assistant-Commandant-for-Human-Resources-CG-1/Health-Safety-and-Work-Life-CG-11/Office-of-Work-Life-CG-111/Sea-Legs/Health-Care/
TRICARE For Life offers secondary coverage to Medicare for all beneficiaries who have both Medicare Part A and B. TRICARE For Life is available worldwide. Medicare provides coverage in the U.S. and U.S. Territories. In all other overseas locations, TRICARE is the primary payer. You may visit any authorized provider. Your provider will file your claims with Medicare. Medicare pays its portion and electronically forwards the claim to TRICARE For Life claims processor. TRICARE For Life then pays the provider directly for TRICARE-covered services. For services covered by both Medicare and TRICARE, Medicare pays first and TRICARE For Life pays your remaining coinsurance for TRICARE-covered services. For services covered by TRICARE but not by Medicare, TRICARE For Life pays first and Medicare pays nothing. You must pay the TRICARE fiscal year deductible and cost shares. For service covered by Medicare but not by TRICARE, Medicare pays first and TRICARE For Life pays nothing. You must pay the Medicare deductible and coinsurance. For services not covered by Medicare or TRICARE, Medicare and TRICARE pay nothing and you must pay the entire bill.