Thanks for this. I use this one-needle two at a time method most and it's wonderful.
But what Ellie was talking about (I think...) is knitting two socks at the same time but one inside the other. It's a type of double knitting that produces two completely separate socks and can be done on circs or double points. It's very magical when you finish and pull one sock out of the inside of the other! What a hoot!
Here's a link to the first article I found on the subject...
I used the method with leg warmers where I didn't have to fiddle with the shaping for heels and toes and it worked like a charm! What a rush!!! But I'm really looking forward to taking some time to try out the whole thing for socks.
Again, thanks for the link. I love it!