NOT an expert opinion here, but I've been thinking to use it in knitting projects too. I've used it, but in crochet, not knitting. IMHO, I think it might be a good replacement for items where durability is an issue....like maybe a tie or a backpack. I don't personally know about doing socks with it though. My guess is that it would be alright for a summer weight sock, but winter? hmmmmmm
From what I've seen, I've been using the granddaddy size of them all; Size 3, Aunt Lydia's Cable Crochet thread, a 200 yard ball of 100% mercerized cotton. It's about as close as it gets to sock weight yarn. I just compared it to my leftover Sockotta and it's pretty close. The recommended hook size is "3.5 mm/7", but I typically use a US size 1 which is 2.25 mm. BTW, 3.5 mm converts to a US size 4 knitting needle. I'm sure larger wouldn't be an issue either. Knit or crochet.
I've looked far and wide and can only find ALCC at Wal-Mart and in Black or White (I've also dyed it to suit my needs...it dyes easily). It also comes in Natural IF you can find it. At the (few) online places I've seen it at, the price is outrageous, so I buy B or W at my local Wally World, for around $2 a skein. At this price you can experiment all you like.
Aunt Lydia's also sells a similar line called Fashion Crochet thread ("3.5 mm/E-4") which is about as plump in diameter as the Cable. It also comes in a much wider variety of colors. I used it once (which a necklace pattern called for), but realized my mistake of buying Cable was even better for the project. I'm not 100% sure what the difference is, other than the name, though the Fashion seems a little more "silky" and a little less stiff to the touch.
If this means anything here, unless I'm horribly mistaken, I've noticed that unlike knitting yarns, sizes in crochet thread vary among the different manufacturers. Size 3 in one brand may not be the same diameter with another. You will find many different makers of this stuff, which comes in a variety of skein (ball or bobbin cone) sizes, depending upon the manufacturer.
You'll definately need small knitting needles to work with it. Perhaps size 2, 3, 4 (rough guess). You might go smaller if you work with the more common sizes of crochet thread (I think it's super tiny, compared to just about ANY yarn).
I would look around the crochet sites to find patterns using the thread or use knitting patterns which (of course) call for sock weight yarn.
In case you find something in crochet, here's a few links that may be helpful:
How to Convert a Crochet Pattern to a Knitting Pattern
How to Convert a Knitting Pattern to a Crochet Pattern
Maybe? a helpful link on converting:
Handy Worldwide knit and crochet needle conversion helpers:
A TON of crochet projects==> have your browser search for "socks"