You're barely scratching the surface of what your Jnat can do if you're only using diamond and Tomo Nagura. A set of Asano Mikawa nagura (Botan, Tenjyou, Mejiro) offers a much greater range of grit/cutting ability. I go straight from a 1k King to Botan Nagura, and work that to remove the 1k striations. If the steel is particularly tough I'll then do a dilution or two with Tenjyou Nagura, otherwise I'll go straight to Mejiro Nagura for the final sharpening - usually 2 or 3 dilutions. After that, I will work Tomo Nagura, refreshing it just as it starts to change color until I'm satisfied with the sharpness; then a final dilution that I work all the way until it's completely broken down. I'll usually test shave before doing any work with just plain water; usually it isn't necessary, but if needed, I usually do less than 20 laps or it starts to get harsh. If 20 laps on plain water won't bring it up, the solution is another full dilution with Tomo Nagura.