I agree with the author: there’s moral value in being clear what we’re doing, and doing so in ways that are as humane as possible.
If you support the death penalty, the most obvious benefit of the firing squad is that unlike lethal injection drugs, correctional institutions are never going to run out of bullets. And if they do, more bullets won’t be very difficult to find. Ammunition companies aren’t susceptible to pressure from anti-death penalty activists, at least not to the degree a pharmaceutical company might be. This would actually remove a barrier to more efficient executions. As someone who would like to see executions eliminated entirely, I don’t personally see this as a benefit. But death penalty supporters might. And there are other benefits to the firing squad, benefits that I think people on both sides of the issue can appreciate.