Ashby says he came up with the Tanto name by visualizing two Tanto knife tips, as in Elkbreaths' upper photo, placed back to back. Elkbreath's sketch shows only the profile view. Grizzly's Tanto is not cut-on-impact, thus Ashby's modification to make it so. With a double-bevel head the Tanto tip is beveled at 30 degrees on both sides, and on both faces, produced a four-sloped tip. With a single-bevel it is beveled only on the edge opposite the blade bevel, if that makes sense. Imagine a single bevelhead head, Face A: The Tanto tip is beveled only on the side or shoulder opposite the blade-edge bevel. Now flip the head over to Face B and do the same. Thus, on each side of the blade you have one beveled cutting-edge, with the opposite Tanto tip shoulder also beveled. This provides a sharp, skip-resistant CoI tip that sacrifices no strength. Ashby has an article with photos illustrating all of this in a future issue of TBM, and having been "gone bush" for research for several weeks now, should be returning soon to TG to explain better what I just tried to explain worse.
As I tell my wife often, "I did the best I could." As she always replies, "That's not good enuf! Perfect ain't my thang. It is Dr. Ashby's. d