I dunno. Kumar sometimes does a fuller length job, as does Sher, but not always. Bura can be very good also. I saw Dave Rishar's picture of an etch that revealed the hardened zone of a Museum model, and I thought that was too small a area. On the other hand, there is this belief or force today in the forum that a full length hardened edge is a better thing. I don't think it is. Certainly not near or on the tip of a working khuk, though appropriate for the conventional knives.
I don't think the hard edge has to extend to the handle, either, on a working khuk. I'm mildly concerned we'd be losing something to demand a full length zone, though admit I don't know what that is exactly. I mean, would such khuks cost more? Or how about more prone to breakage at the handle? Does the softer metal to either side of the hardened zone act as a buffer, both in shock and in protecting the integrity of the hardened zone? In other words, does the flex to each side of the zone protect the stiffer, more brittle edge? I don't know. There are probably good reasons why one should not have a completely hardened edge from the handle to tip of a khuk, though a more generous length seems good to me. I thought Kesar was sometimes a little stingy in his zones. I like a little over because then as I chop it's easier to get value out of a slight miss from the sweet spot. There's no doubt that for chopping, just like the sweet zone of a baseball bat, going too far up or too low is non- productive. Kamis have been making this design hundreds of years for a reason.
HI's conventional knives are being hardened full length, I hope. That is what Yangdu asked the kamis to do.
munk