When House Republicans last week narrowly passed the latest version of their Obamacare replacement, the American Health Care Act (AHCA), much of the attention was on the last-minute amendment inserted by Rep. Tom MacArthur (R-NJ). On its surface, the amendment appeared to create a waiver for Obamacare’s “community rating” regulation, and would now allow insurers in conservative states like Texas or Arizona to return to the pre-Obamacare days of charging more to customers with preexisting medical conditions.