I have recently been knitting with a skein of Wollmeise. I've owned some of this rare and highly-sought-after yarn for nearly a year, and just recently began actually knitting some. This skein is not actually my skein. I'm knitting the socks as trade.
I soon discovered a problem with the yarn. It's overtwisted. Way overtwisted. Twisted enough that the stitches won't sit straight, causing the socks to twist diagonally. It was unsightly and unacceptable. To solve this, I wound up letting the sock dangle every half row and spin out the overtwist. Consequently, I can't knit the socks two at a time, because they can't untwist when they're joined. And even worse, the knitting takes a lot longer because you're stopping every half row.
To test the twist of the yarn, I hold two spots on the yarn, and bring the dangling strands together. If they twist around themselves, they have too much twist. I pay attention to the direction the strands spin, and that's the direction I spin the sock.
If you hold the dangling strands close to each other and they just hang there, not twisting around each other, then the yarn is fine for knitting.
Perhaps the overtwist is a defining characteristic of this expensive yarn, but I couldn't knit with it that way. The knitted product was sloppy and twisty. It's been a long process, knitting these socks while untwisting the yarn, but I'm nearly there.