Late in his second term, George W. Bush signed into law the Energy Independence and Security Act of 2007, which requires light bulb makers to improve the efficiency of incandescent bulbs by 25 percent. The details of the law dictated a phase-out of the manufacture of certain bulbs in their current incarnation, starting with 100-watt bulbs next January.

The law does not ban the use or manufacture of all incandescent bulbs, nor does it mandate the use of compact fluorescent ones. It simply requires that companies make some of their incandescent bulbs work a bit better, meeting a series of rolling deadlines between 2012 and 2014.

Furthermore, all sorts of exemptions are written into the law, which means that all sorts of bulbs are getting a free pass and can keep their energy-guzzling ways indefinitely, including “specialty bulbs” like the Edison bulbs favored by Mr. Henault, as well as three-way bulbs, silver-bottomed bulbs, chandelier bulbs, refrigerator bulbs, plant lights and many, many others.

Nonetheless, as the deadline for the first phase of the legislation looms, light bulb confusion — even profound light bulb anxiety — is roiling the minds of many.