Unfortunately the best shortcut to a fine finish seems to be sand until you are sick to death of it, and then sand some more. I go to 1k grit on my user knives; 2k on Hamons, and 2k on handles; all by hand. My grit progression is 220/320/400/600/800/1000/1200/1500/2000. It seems to take forever to get to 600 but after that it all goes pretty fast if I have properly sanded with the prior grits. Still, It takes about 4-6 hours per blade, sometimes more; especially if I get in a hurry.
Hurry = takes more time than it would have to patiently do it right the first time.