Hi Steve,
Welcome to the forum! I had to read this thread several times before I managed to absorb all the great informataion.
You should not mix your macros and micros in the same bottle, but you can certainly dose them at the same time. I simply dump them into the spoon (or use the pipette, for smaller tanks) then rinse by swishing in the tank and dose the other a few inches away from the first.
I have only had precipitates form once, and that was when I dosed one and immediately spilled the other right on it.
Good luck using PPS Pro. I have used it since January and love it. I still do water changes because I have an overload of fish in my tank.