And that I suppose is Nagash's trick. How a human can approach the power of the Dark Elves wielding True Dhar without an Elf's multiplexed mind to crush the winds into a single perfect shape instantly. Take ONE thread and weave it with that one thread of singular focus.
Weave it with the patience and focus of a literal priest, which both Frederick and Nagash were.
The description actually sounds a little like making tempered glass.
This has interesting, and frightening, implications in regards to the craft of the Chaos Dwarfs.
Because "work it slowly, carefully, exactly and patiently" is something Dwarfs would be good at. And if good Dwarfs are able to manipulate magic so finely that they can take all the different winds of magic and turn it into something... tamed... achieving something interestingly comparable to elf Qhaysh... Then evil Dwarfs being able to apply that expertise to the manipulation of
Dhar, well...
So. Yeah. Either the Chaos Dwarfs already know the First Secret of Dhar -- just by independently stumbling upon it, due to a Dwarf mindset being well disposed towards doing so -- or them learning it would be
really damn bad.
Of course, on the other hand -- Dwarf Runesmiths learning of the Second Secret of Dhar... Well. You'd be able to trust Dwarfs with the first two secrets of it. Especially Runesmiths or Runelords, who already are secretive as hell.
Of course the issue would be figuring out how to communicate such knowledge to the Dwarfs. i.e. The fact that
you somehow know all this. In a way that doesn't come back to bite you. (I mean, maybe it's easier because unlike other wizards who would know the issue with "How the fuck did you just do that??" the Dwarfs might not know it. So it's not necessary to come up with the same excuses that you would for a wizard.) But still. If it were managed, then... it could be quite useful. Dwarf Runesmiths would be able to shatter entire armies of Necromancers and constructs of Dark Magic.
Of course, it might not work. Maybe the Dwarfs already know this, and it's how they counterspell with their Anvils of Doom to begin with. Or maybe the Dwarfs, being unable to see magic, would not be able to see
where to hit Dark Magic in that one spot that will make it unravel explosively. Or maybe there's no easy excuse to find for why you would know such magic.
Or, for that matter, maybe trying to teach something, or even just demonstrate and give information about, to a Runelord is an exercise in frustration/futility and ain't gonna get you
shit. Still, there's probably more ways to be able to pass on information than just by trying to bluntly tell somebody about it.
But if it did work... The possibility and potential is interesting. Because I'm willing to bet that this situation -- of the Dwarfs having a friendly wizard and trusted, and said wizard having access to the Liber Mortis -- has
never come up before. So the Dwarfs have never been in a position to receive such knowledge.