@robpike @timbray Y'all remember when they first advertised URLs on broadcast TV?
I distinctly recall a mid-90s ad from Ford which literally said:
Haich Tee Tee Pee Double Dot Forward Slash Forward Slash Double-U Double U double-U dot ...etc
They spelled out "Forward Slash" presumably because the target market were Windows users who traditionally believe that the "One True Slash" is the backslash.
Presumably the spelled out colon as "Double Dot" so as not to offend genteel folk and chilluns.