Years ago I knew someone who came up with what I thought was a great idea. He took the gas line of a car and inserted a steel tube. Surrounding the tube where the fuel flowed was another tube, one he was able to plug that into the radiator line. That way, very hot water would heat up the 3-4-inch tube through which the fuel flowed. The idea was simple: make cold fuel hot before it went into the cylinder and fuel efficiency would soar. You'd also get a cleaner burn.
Great idea except it didn't seem to work. It was an idea that they'd had in World War II to extend the range of torpedos, except it didn't quite work that well then, either. Still, he sold quite a few before the state made him stop. But what the heck, I was a big believer. It was such a great idea that it never occurred to me to actually test it.
San Mai is one of those things that I think works well on paper. But instead of gaining the strengths of three various steels, I worry about getting the weaknesses of the three types of steel instead. The idea is good, but I'm not sure the concept has ever been tested.
Cold Steel's website says, for example: "A simple way to think of this type of construction is to imagine a sandwich: The meat center is hard, high carbon steel and the pieces of bread on either side are the lower-carbon, tough side panels. Generally the edge of the blade should be hard to maximize edge holding ability, but if the entire blade was hard it could be damaged during the rigors of battle."
But what kind of center? What's the Rockwell hardness of the core? Is it 59? How about 60? Will sandwiching it in tough cheaper steel also make the core tough? Well, what would happen if you took glass and coated it with steel?
The best bet, I'd think, would be to use a good premium steel like VG-10, S 30V or 154 CM and then really watch the quality control. Sure it's harder to sharpen, but I don't see people with them complaining. Maybe it's because they're not sharpening their blades that often.
If the center steel is brittle, I think the layers wouldn't be enough to absorb the shock. In short, I hate to say it, but until someone tests it, I'd say San Mai = snake oil. I certainly wouldn't spend the large amounts of money on something that hadn't been tested.
