I don’t know how their logarithm works. But layer height does matter, because it generally affects the printing speed and the volumetric flow. The optimal pressure advance settings for different flows varies!
I’d really like to know how they calculate it, and it would be awesome if you could do a flow calibration on the specific different speeds, layer heights etc that you use, and store the values to the filament. Having it adaptive would be best, if you are using adaptive layer height, I do believe it could matter quite a bit?