That's a great article. I am surprised that for light work loft is 0.8 inches at 40degF, but I see that is for torso. Perhaps it can be less for even coverage. In winter at 40F doing light duty I tend to be unevenly covered, unless its windy, because I am saving some other layers for colder temperatures and so I might undress unevenly, like medium sweater and hiking shorts. In summer when its 40F doing light duty it probably after dark and I am likely to have all my layers on except my rain layer, so it would be fairly evenly distributed, and likely less than 0.8 inches, perhaps 0.4 inches, like a skin layer and thin merino sweater and wind jacket. Of course even a light merino sweater and wind layer can puff up a bit, but that's hard to measure until you get reasonably thick, as in winter.

Any good tables on total clothing weight as a function of minimum expected temperature. Tricky thing is that minimum expected temperature in summer tends to be wet, whereas the minimum expected temperature in winter tends to be dry, at least if the minimum expected temperature is well below freezing. It might be best to add an extra pound if the minimum expected temperature is above 20F, but then you might need to add an extra pound below 20F also for other reasons, like the body's heat storage reserve is relatively less, so you might need that extra just to warm back up after doing something.