My impact driver doesn't have a variable torque setting but my cordless drill does. I don't know how someone can argue with that, but you do.
I have an Ingersoll-Rand 1/2" drive pneumatic impact in my work box, a HF Earthquake 1/2" pneumatic at home, a 3/8" Rodac butterfly impact I bought 40 years ago from a neighbor, a 12V HF electric impact in the trunk of my car for changing tires, and a cordless Ridgid impact driver as part of an 18V set I bought a few years back. The pneumatic tools I can regulate, not so the electric tools that I have. I know how they work, I've taken them apart before (the butterfly has a tendency to stick) but thanks for the reminder.
I was talking about torque, and you inferred impact because of Bruce's video that I linked. I haven't needed to use Bruce's method, but thought someone else might find it helpful.