I have no expectation of being able to do what real artists have accomplished with Ernst Fuch's mische technique (see http://brigidmarlin.com/ ) but after some time fumbling with ways to get similar effects via cheating, I think I've got it:
The bottom picture here is an underpainting of watercolor pigments mixed with acrylic glazing medium; the first one is what this looks like after adding a layer of vinyl acetate sizing and some fairly transparent oil painting.
