>> I think you may need to soak it well first, but really, anything you expect to wick would be soaked first.
I agree. Also, maybe they need to be washed a little to get any sizing out.
When I ask clerks at fabric stores what fabrics would absorb water well and make good wicks, they look at me like I'm speaking Urdu. One suggested that "cotton absorbs water", No one came close to "microfibers" or had opinions about polypropylene, nylon, etc.
I think that hugely thick, loosely formed yarn would be good for wicks, but all the yarn I saw was wool (expensive) or acrylic, or polyester. And each big hank was $5 or more, so i didn't want to buy several and experiment.
Cotton flannel works for what I've used it for, so far.