Wovember, a month-long celebration of wool, wool yarn, and wool garments. Cuddle up in your woolies and spare a thought for our wonderful sheep!
After years of flirting with other fibers, these days I knit almost exclusively with wool. It may be wool mixed with a bit of silk (as in Elsebeth Lavold's wonderful Silky Wool) or wool with a bit of nylon (as in sock yarn). But I find that the less wool in the yarn, the less happy I am with the results.
From the perspective of a pragmatic knitter, wool just gives the best results, both short-term and long term. Oh the projects that have flopped because they were knit in a fiber without bounce or grip. Like the 100% baby alpaca scarf that turned into a sad curly rope twice as long, after being worn twice. Or the mostly-silk hat that sagged and never un-sagged. Or the cell phone cozy knit in a bamboo yarn that sagged until it was about three feet long.
Wool's crimp and memory helps it spring back after the insults of wearing. (Damn that gravity!) And the scales on the fiber help keep it from sagging in the first place. All the stitches grip each other, which helps them resist the pull of gravity.
Wool stitches also sort themselves nicely after a quick blocking. When I was a new knitter, I loved that a 100% acrylic piece didn't have to be blocked before I gifted it. Saves me a step! But with more experience, I came to love the blocking process. Sure it does magic things to lace projects. But even a humble stockinette hat will have a much improved appearance after blocking - assuming you knit it in wool. It's like the wool WANTS you to succeed, so if you get it damp and pat it into shape, it will obligingly settle all its stitches to look better than they did before.
On the rare occasions when I knit with a non-wool fiber, at least half the time I carry along a strand of wool yarn, too. I recently knit a hat with Cascade Pastazza, which is 50% llama/50% wool. I knew it would be liable to sag out of shape, so I knit it with a strand of Cascade 220, which is 100% wool. (And very affordable!) The 220 helps hold the lovely Pastazza in shape, and keeps it in line.
All hail the sheep!