I believe he understands, but you don't seem to.
The H&W plans ran the numbers. Ran the projections for the next 5 years, including cost increases. They came up with the number that $0.50/hr will cover the H&W for the next 5 years and the plans will maintain the same coverage.
5 years down the road, when a new contract will be negotiated, those numbers may change. That will be taken up in the next contract. For the time being, the actuary's came up with a number to maintain H&W for the next 5 years.
I know you think it is not right, and it's a concession, but they ran the numbers. And they know a helluva lot more than you and me.