Sock it to 'em
It's one of those questions that doesn't get asked everyday, but when it is, the enquirer doesn't usually have to finish their question before we can help them. They usually start with
"I don't know if you can help me, I was in the World War 1 section and noticed a knitting pattern for..."
At this point I can jump in with:
"Knitting two socks at once."
As a knitter whose skills would be best categorised as advanced beginner, the opening sentence of the pamphlet (0.40Mb PDF file):
"This method can soon be learnt by anyone already expert in sock-knitting, but should not be attempted by beginners."
has been enough to discourage me from attempting to knit two socks at once, although many of our visitors seem willing to take on the challenge.
I think if the urge to advance my knitting expertise using wartime knitting patterns strikes, I'll start with mittens (0.14Mb PDF file).