Just going back on topic. Let me start by saying forget the different layers, what others think of them etc.. Since this thread is about Coticules then that's what I'll talk about. The results others get will differ from the results you get and vice versa.
Facts:
-You can get a fantastic La Verte, and you can also get a not so great La Verte. Let's not forget that they are a natural form of matter.
-Coticule slurry does not break down and become finer, this is what makes them tricky due to slurry dulling (will discuss slurry dulling in a different thread). The refinement is reluctant on your progression within the one, what I mean by that is, the quality of your strokes, your stroke counts, your pressure, how well you are able to determine feedback, how well you dilute etc..
- With good practice, time and patience you can get a good edge from a coticule, it's not going to be anywhere near as sharp as synthetics, in fact, the keenness is similar to what you'd get from a naniwa 8k but the smoothness, versatility and speed is what they are known for.
How do you use a coti? this will take me a while so I'll include some useful videos and discuss the methods if any of you end up with one.
Let's put all this aside and go back a step. This was said by a member of a honing forum " Synthetics are science and Naturals are romance". This is true in the hands of a new honer. Naturals will behave differently with different steels and give you different results. Synthetics will be consistent and behave the same way with every razor.
If you're new to the honing game, hold your horses, get the basics right such as bevel setting, good strokes and know the exact purpose of every progression used in your kit before jumping on natural stones, that's just my take, your choice of course. If you have someone to guide you through your stone, preferably someone who has already tested it would be a big bonus.
If you're not new to honing then you probably don't need to read half of this. Instead you'll be busy trying and buying different stones when you can, there's no way of telling what you are going to get when you buy a natural stone until you try it, you only have an idea. Don't let this put you off naturals but my best advice it to get them from a vendor who has lots of experience with what they're selling and have tested and analysed each individual one with a razor. Or to simply buy one from a person that uses them for the same purpose as yourself.
Here are some videos that I found to be the most informative when it comes to coticules. Credit goes to Gary Haywood, the best coticule honer I know for passing his knowledge to me about using coticules who also sold me my first coti. Hope this helps. Cheers.
Gary Haywood using a Coticule
Dr Matt (3 parts, here is part 1)