the verticle stripping is IIW. i would probably fire then cut these in with a bur then fill with IIW. or you can just build your skin layer and wipe a thin brush across then fill in with IIW, you just have less controll that way.
If you use something like OE4 i think you will find they come out to faint unlless you have lots of space and can make the embrasures to fill with white very deep, and you will have to bump them up with white stain at the end, which is not a major problem.
Yes the I enamels are less translucent. It depends on how you build up, i do one build of dentines and a base incisal in I then fire. Then use TI or I as a skin layer.
if you use the TI's right through then you will probably find there normally to translucent and grey to much or you have to much of a demarcation where the dentine ends and the enamel starts.
Alternativly you can just chuck 5%-10% dentine into the TI enamel.
Dont frighten your self by looking at the shade tabs for IIW and thinking wow that is gonna come out way to white. Remember the Tabs are like 1mm thick, even at their thinesst part. The space we have when working with the enamel layer on a build is way less than that so if you image that colour at maybe .2 then that is how intense it will be.
To get white motteling like the image there, you need to start using the essence powders to boost the colours, or use stains to boost em.
as always better to slightly under do than over. You can always bolster with external stains at the end. Once the underlying colour is there, it only takes a small amount of stain to bring the colour out.
After rubber wheeling smooth then stippling with a bur, use a thin wash of glaze and fire at 70 climb at 730 with 0 hold. That should get you close to that luster i reckon (providing your furnace is accurate). If you over glaze out the furnace its gonna be hard to bring back down without screwing your surface texture, so under glaze and buff up with diamond paste is the way to go.
oh and the essence powders are VERY intense. So if you get into using them normally a very small amount, say 5% is plenty in the mix.
Phew! My 2 cents
See if Al or someone has anything to add, or maybe they will think different.
"No experience with the effect powders either. I need to find a really good course for that."
Check when IDEA has Oliver Brix out there again next, and learn from THE MAN