When I was working at making TONS of sausages( at a company) I thought Id do a test I grabbed some meat patty mix about the size of a burger patty and left it in fridge over night it browned up a bit so did the same the next day but put a VERY tiny amount of cure on it like a few grains just that lil bit made a red spot over night about the size of a quarter, so made me think you dont need much to cure some meat and it defiantly spread...YEAH I know too much thinking but when I do stuff I want to know all the ins and outs as much as possible..
So when you do bacon and it sits for 8 to 12 days im sure that stuff is doing its thing as EVEN thru that thick of meat it cures and ive never seen any brown what so ever on my bacon...look at how thick this piece was and anyone who knows me i have big hands