Tim,

You may not be able to get the HHT to work after the D8EE. As long as the blade feels "sticky sharp" against a dry thumbpad you should be ready to move on to the 12k.

From there, I'd recommend using the D8EE as a "nagura" to start a thin slurry on the 12k, it'll speed things up a bit. After the blade has gotten a decent polish from the 12k w/ slurry, wash the stone off and finish w/ just water as a lubricant (30 passes or so).