Seldom if ever, do I need to include the cyan filter when printing a standard neg onto normal RA4 paper. All three filters should only be needed when adding density. One filter will always be set to zero (generally cyan), because the other two can create the same filtration of the the third.
Ed, I am assuming that you know that any amount of Cyan added to a filter pack is equivalent to an equal amount subtracted from Y and M (eg. +10c = -10y and -10m).
I always start my filter pack at 50y, 50m, 0c when printing a new neg, but I almost never finish there.
ekjt, 102,5Y 92,5M is not an unusual filter pack. if 50y,50m is a conventional starting point, 0y, 0m, 10c (the inverse of your filter pack from 50y,50m) would be far more unusual.
As I read this thread I would follow Photo Engineer's opinion as he/she appears to really know his/her poop.