any attempt of doucing in water or oil would be an attempt of tempering the coin, or adjusting the hardness of the metal...a QUICKENING so to speak..though I don't know of its use for pre-pairing dies, as annealing is meant to soften the dies while there are being prepaired for there imprints,
how ever there is a relationship in all of these processes, annealing, softening,of the hubs in order to get the fullest of details in the master hub, which will produce the die, and a die also of such softness to to take the imprint of the hub, yet it also needs to be in the end to be of enough hardness to stamp the coins for an assumed number of strikes,as an average expectation that is......so in the instance we must think of the separation of the hub process and the die process....
as each requires something different.......for those differences, I will stop here.........and examine your thoughts on this as well.......mind you we have not even gotten far enough in these thoughts to explore the die crack phenominum yet to be considered, but it is relevant at this point, as is cause is to effect....