When I was first able to compete and complete Find recruits II, I never realised exactly how lucky i really was. In just 3 or 4 months (+?), I pulled 6 x green 4 star mana troops, 3 x 4 star critical attack troops; one of each in Red and one of each in Blue. No yellow, no purple. The 4 months or so after that have yielded just 1 x Green critical and 1 x Red critical.
I am starting to despair. I ran out of feeder troops at lvl 6 for RGB criticals and levels 11, 11, 9 for RGB mana troops. I still have my collection of Yellow and Purple 1, 2 and 3 stars; they will only ever be food for 4 stars. They are too precious to waste.
EDIT: These are the only troops of mine of any consequence. The answer is yes; I did feed away a number of duplicates before realising that was insanely stupid (they are worth 400 pts each).