>>>That aside, let us take the claim as a possible truth. I'm sure that 8 mm maximum diameter of the bile duct is an average number, so some people could pass larger than this.
No, actually that is the maximum. The average is 2-4mm.<<<
I am quite aware there are more ducts throughout the liver and gallbladder than the CBD. However, I assumed (perhaps erroneously) that your reply was referring to the CBD, since the original poster's reference to the 'bile duct' *was* the common bile duct. If I did assume erroneously, then please clarify specifically which duct you were referring to that has an average diameter of 2-4mm and a maximum diameter of 8mm.