I assume there's a bit of outdated information in that article, or the annoyingly common issue of journalists misunderstanding actual research results - the claimed efficiency of ~14% for LEDs seems much too low, the latest LED lamps produce 10-15x the light per watt as incandescent, not the 3x claimed there.
And that's already including the power supply, which is where the majority of the loss is rather than the LEDs themselves, which generally are 80-90% efficient. But that's mostly a cost limit rather than a technology issue, as there are known better designs, just more expensive to implement.
I'm seeing about 2% efficiency for incandescent, 20% for LED, and 40% (claimed) in that article for the experimental incandescent. That tracks with your 10-15x number and would still be twice as efficient. I am assuming it would be cost related, but can't find any info and wanted to see if others knew.
And that's already including the power supply, which is where the majority of the loss is rather than the LEDs themselves, which generally are 80-90% efficient. But that's mostly a cost limit rather than a technology issue, as there are known better designs, just more expensive to implement.