All About Pocket Knives

I have a Case 33092 that has double stamp on the tang. The stamp is Case XX USA with 2 dots. Very visible. Actually looks like 4 dots. Does this increase or decrease value or make no difference.
The knife is not a carry knife never sharpened but does have a few discoloration spots on blades.

I for one have heard that it does increase the value slightly if indeed it is orginal, but I have never seen one and wouldn't buy a knife for that reason. I guess this is a roll over from coin collecting. With so many concerns about counterfieting, I would hope that it didn't start a craze if crooks thought we would pay more for them!!!! Just my thoughts though