Why does the saw-tooth count on Randall Knives vary so much from knife to knife. I counted mine it has 21 teeth. I've found from looking at others twenty one different model 18's they vary from 25 to as low as 11.They were new and older models with 7 1/2 ss and carbon blades, Solingen. 17 teeth is the most common with 5 of the 21. So I was just wondering if anyone knows why.