Ah the V-Tool. It has a reputation for being the most difficult carving tool to sharpen, but I commissioned my Ashley Iles 3/8" 60 degree v-tool on diamond plates followed by oil stones and I didn't find it that difficult really. Time consuming yes, but not difficult. Since then I have a bought a Tormek T8 with the standard synthetic SG250 wheel, the Japanese waterstone wheel and the course, fine and Extra fine diamond wheels. After I finished my Three Hares carving, I decided that I was going on a mission to buy all the carving tools I would ever need. I now have around 180 tools with about 50 still awaiting commissioning. I try to commission 4 or 5 of tools each week before I start work. Anyhow, the reason I bring this up is that I use the side of the diamond wheels (not the circumference) to shape the tool and lower the cutting angle to where it feels good in my hands. Like you, I don't measure the angle. I have recently innovated a genius solution (if I do say so myself) to sharpening on the side of the diamond wheels which I hope to do a video about shortly, before posting it here. Pointless posting the project yet as nobody would have a clue what it was without the video. LOL.
Andy -- Old Chinese proverb say: If you think something can't be done, don't interrupt man who is doing it.