As in-the-weeds as a revised waiver process sounds, the practical effects of what the Trump administration announced yesterday could add up to one of its most substantive blows yet against the Affordable Care Act.

The big picture: These changes will likely cause more separation of healthy and sick people, but only in states that avail themselves of these new options — creating another level of segmentation between red and blue states.

How it works: Under the Obama administration, states seeking a waiver from the ACA’s rules had to show that their alternatives would cover just as many people as the ACA, with insurance that’s just as robust, for the same cost. That’s why only 8 waivers have ever been granted.

• But under the Trump administration’s approach, if the same number of people have access to ACA-level coverage, that’ll count — even if few of them actually choose it.
• Likewise, “a waiver that makes coverage much more affordable for some people and only slightly more costly for a larger number of people would likely meet” the new standards, the formal policy guidance says.
• States could, for example, seek a waiver that would let their residents apply the ACA’s premium subsidies to “short-term” insurance plans, even though those plans don’t meet the ACA’s requirements, including the mandate to cover people with pre-existing conditions.

Between the lines: The Trump administration has often treated the ACA’s exchanges as a de facto high-risk pool. And that’s the best prism through which to understand these latest changes.

• These waivers will let states lean even further into new, non-ACA options for healthy people. That will likely increase premiums for ACA coverage. But because the vast majority of ACA enrollees are subsidized, they’ll be insulated from those costs.

There are limits to how far that dynamic can go, because states' waivers still can’t add too much to the federal government’s costs. But that’s the basic dynamic at play here — and it’s one that will continue to move the larger individual market further and further away from the ACA.