Will it work similar to an Arkansas, and polish finer if well burnished? Sure. But every time you rub a nagura over the surface, you're disturbing that burnish by releasing some of the surface grit on the hone whether you're using Tomo or something softer. So...are you willing to burnish your hard Jnat and never touch that surface with a nagura again?

Besides, when you think about it your Jnat will typically be polished according to the nagura you're using in concert with it. Mine stays polished to somewhere in the 4 to 6k range, and that's well beyond what most do to their Arkansas stones.