Not familiar with totl in-ears, but pretty wowed by this article. Happy we have an in-ear guy in John who's heard everything.
It's an interesting thought experiment to consider a model like this for mixing and mastering. In-ears seem to remove the most variables and get you as close to the material as possible. That could be optimal for translation purposes. Easiest image to wrap your brain around.
I'd imagine there's less pair-to-pair variability given the way in-ears are designed. John can you comment on that at all perhaps?
Further- is custom cabling easy with these? How's that tend to work?
Best