Insurance companies are easy for the media to demonize in the abstract. But when it comes to revealing how they operate—well, that’s harder. They’re a pretty secretive bunch these days, even as they’re constantly in the news amid the rollout of the new health exchanges.

So it was great to see Dylan Scott at Talking Points Memo dissect what insurers are up to this week in a piece that shed some light on the choices faced by shoppers on the individual market who—contrary to President Obama’s pledges—are finding they can’t keep their current plan.

Scott reported:

Across the country insurance companies, have sent misleading letters to consumers, trying to lock them into the companies’ own, sometimes more expensive health insurance plans rather than let them shop for insurance and tax credits on the Obamacare marketplaces… In some cases, mentions of the marketplace in those letters are relegated to a mere footnote, which can be easily overlooked.

Indeed they can be—and important stuff, like the subsidies, can even be omitted entirely as companies seek to persuade (some of) their policyholders to stick with them awhile longer. This summer we found that Aetna had failed to disclose to a woman whose policy the company was cancelling that she might be eligible for subsidies. And in August, we detected hints that consumers were being pushed by brokers, too, to lock in plans that might turn out to be higher-priced or less comprehensive than what they could get by waiting to shop on the exchanges. (The details of the comparison depend, of course, on each customer’s needs and circumstances—something that has often gotten lost amid the media’s belated discovery of plan cancellations.)

The strength of Scott’s piece is the discussion of the marketing practices of two insurers: LifeWise, a subsidiary of Blue Cross/Blue Shield in Washington state, and Humana, a one-time regional carrier that became a national powerhouse after latching on to the Medicare drug benefit that arrived in 2006. LifeWise, it seems, was cancelling policies and switching policyholders to a new plan that was the “closest match” to their old one. The letter one woman got—posted to Scribd by TPM—said: “If we don’t hear from you, we’ll automatically move you to this plan and you’ll be covered starting January 1, 2014.” It made no mention of the state exchange where people might find something better or cheaper than the plan the company suggested. A spokesperson for the carrier told TPM, “Our experience is that our customers are already aware that they have other options in the market and that we’ve never had to tell them in the past that we have competitors.”

As for Humana, it, too, sent their customers letters downplaying the fact they had other options in the state exchanges—including cheaper plans from Humana—or could qualify for subsidies. Shades of Aetna! A footnote in the letter mentioned the “open enrollment period” that began in October but didn’t name the state’s marketplace or directly mention the availability of subsidies. Humana declined to talk to TPM but sent a statement saying, “In retrospect, the letter could have been more consumer friendly and we’ve rewritten it with that in mind.” (Both Humana and LifeWise were also discussed in an earlier Sept. 23 article in The Wall Street Journal, linked to by Scott, which is somewhat more sympathetic to the insurance companies.)

Scott’s story is a tale of insurance regulation as much as it is about corporate practices and customers in the dark. It points up the differences in regulation and the protections, or lack of them, shoppers have in different states. Good insurance regulation is crucial to making the Affordable Care Act work. It’s a neglected and underreported topic, and it shouldn’t be.

Trudy Lieberman is a fellow at the Center for Advancing Health and a longtime contributing editor to the Columbia Journalism Review. She is the lead writer for The Second Opinion, CJR’s healthcare desk, which is part of our United States Project on the coverage of politics and policy. Follow her on Twitter @Trudy_Lieberman.