Byron, my interpretation is that it's not so much a matter of specifically trying to get a convex bevel, it's more a matter of not obsessing so much over a flat bevel. Don't need laser-guided GPS-enabled jigs. Just let it fly. The convex bevel is then the logical consequence. Rather than fearing the curve, embrace it.
The one definite issue with a flat bevel is that it has to be repeatable. Once you've carefully gotten a 30 degree bevel on there, if the next time you hone it you only get to 29.9, you may not actually be resharpening it. Or you end up having to take off a lot more metal. That was definitely one of my complaints with using a jig. I found all that fussing about annoying and unnecessarily time-consuming. I wanted to get back to working the wood.
And I'm sure blood is an effective honing medium
(I
am up to date on my tetanus shot).
This method did indeed work equally well on DMTs. I have a couple of reasons for not using them.
One is that I'm trying to get my hand tool skills down to bare essentials. My particular obsession is to be able to work the way someone in the 1800's did; I admire that versatility and self-reliance. As a hobbyist I'm clearly romanticizing that aspect a bit, because some of these tasks done hour after hour, day after day would be crippling labor. Hand-ripping a rough 8' plank is fun; hand-ripping 1000 of them will kill you. But the India stones appeal more to my desire for traditional methods than the DMTs. Norton probably uses laser-guided GPS-enabled robotic cutters to produce them!
Second, when people ask me how to do stuff, instead of telling them to go spend $250 on high-tech sharpening stones (and watch their eyes pop out of their heads), I can honestly offer them a reasonable alternative that only costs half as much (less popping). I realize it's an investment, but it's possible to buy in at different levels.