It seems to me the only way to forecast this storm is to start with QPF and move backward. So, if you are projecting, say, 2 inches is liquid and you are projecting 2 inches of snow, you’ve still got 1.8 of QPF to spend.
It must be nice to speak so authoritatively on a subject so few have been able to fully grasp. I envy that. True clarity is much harder for me. By the way, you opened a parenthesis and didn’t close it.