I've got two coticules that I've been unable to figure out, so I completely understand the frustration of the OP. It definitely helps having a 1k stone for bevel setting, but even then my results have been sub-par. I'm determined to figure them out, but coticules are some of the weirdest natural stones that I've worked with yet. One of mine is super slow on just water, but add the smallest amount of slurry and it will dull the edge quicker than quick. The other seems pretty fast (slurried, it will start to darken in 10 or 15 strokes) but I haven't been able to get a shaveable edge off of it either. I recently tried finishing on glycerin, and the results were terrible. I've even taken Glen's advice and tried finishing a Sheffield blade on a coti, and while it shaved, it sure wasn't fun.

I've said it before, and I'll say it again: If I'd started honing with a coticule, I probably would have quit a long time ago. I was getting good edges off my Nortons within a week of starting to learn how to hone, and they've gotten a lot better since then. The cotis are a different beast altogether, and there seems to be so much variation between each one that you just have to play with them until you get them figured out.... which is a difficult prospect for a noob honer.