Re:I thought there was a point to the two slashes (Score 1)

I remember stating that originally, an indication of which network protocol to use was meant to go between the slashes.

I don't think so, since the double slashes only apply to Internet schemes anyway. RFC1738 says:

//<user>:<password>@<host>:<port>/<url-path>

      Some or all of the parts "<user>:<password>@", ":<password>",

      ":<port>", and "/<url-path>" may be excluded. The scheme specific

      data start with a double slash "//" to indicate that it complies with

      the common Internet scheme syntax.

But if you find another reference, please let me know.

The only place where I know of that being used is in AFP URLs where you can specify AppleTalk using the following syntax: afp:/at/[user[;AUTH=uamname][:password]@]servername[:zonename]/volume

This is referred to in:
http://tools.ietf.org/html/draft-ietf-svrloc-afp-service-01
as well as:
http://en.wikipedia.org/wiki/URI_scheme#Unofficial_but_common_URI_schemes