FAA issues its fair share of airworthiness directives, but few carry the weight contained in this one.
On its surface, it's straightforward: Boeing 787 operators must modify the aircraft's battery system (or take other safety-enhancing actions) via a method approved by the FAA, and do it before further flight.
The catch, as anybody who spends time here on Planet AvWeek surely knows, is that there isn't an approved fix to whatever is ailing the 787. FAA said as much in a press release that explains the directive--a release that's as carefully headlined as its AD is worded.
On deals like this, it's a good thing we have headline writers to cut to the chase.