On: How the World's First Computer Was Rescued from th...

[ncmncm]

GCHQ are embarrassed because they lost / destroyed it. "Refusing" is less embarrassing than "ooopsie!".

[sep_field → ncmncm]

do you have a source for this? I imagine you are right, but is there an interesting story about it you've seen?

[ncmncm → sep_field]

I recommend "Between Silk and Cyanide" by Leo Marks.