? So all their talk about not being particularly good with machines was just a smokescreen?
There have been many interpretations of Klingon history, and many are possible with the scant canon evidence, but it would be a bit odd of the Klingons to attribute the mythical forging of the first sword to some guy who had a space shuttle in his garage (even if it was owned by a Hur'Q and Kahless was just his chauffeur - until the day he took out the tire iron and rearranged the working relationship, of course). Many of the myths about Kahless are medieval in their technological context, with swords and walls as centerpieces. Even if this is just an alien way of living and the swords and walls coexisted with disruptor rifles and anti-spacecraft batteries, it's remarkable that in turn none of the myths have an explicit space age technological context...
One would thus think it likely that Kahless lived either before Klingons were spacefaring or starfaring, or then in an era when Klingons had been forced down from the stars and subjugated so completely that they had to resort to using swords and walls again.