Digital BW, The Print

It's getting late in this part of the world.  So here is an equally 
dumb question to go with the current state of my brain.

MIS sells base stock for mixing your own inks.  If I want to 
experiment, can't I just mix black with distilled water?  Or is the 
viscosity of the inks such that you *need* the base stock?

Also, before I go reinventing the wheel, has anyone tried making 
their own quads based on diluting Gen4 black?  How are the blacks?  
Any metamerism?  How about longevity?

K2