Hi Nichael, thanks for posting that information - interesting article. I'm not one of the researchers so I can't give you additional information on nanotube technology. But, I can tell you about the difference between "hardness" and "toughness":

Hard substances are brittle. For instance: Steel is hardened by quenching it in water or oil from a high temerature. The sudden change in temperature leaves stress/carbides in the steel that are very, very hard. But, hardened steel is brittle and prone to chip and break. So many tools are tempered (softened) slightly to improve their toughness. Tempering dissolves some of the carbide and makes the tool less prone to chips and breakage. So the answer to your question is: No, harder does not equal stronger.

Hey, for all we know the writer of that story got the facts wrong anyway and it will be years before any of us really knows the attributes of nanotubes Makes me want to build a microscopic kayak!