Here are some results, I got so far:
Firefox (Version 28.0)
: YES (sends two slashes)curl
(and I hope therefore also programs usinglibcurl
): YES (sends two slashes)wget
: YES (sends two slashes)Chromium (Version 33.0)
: YES (sends two slashes)
Unfortunately I have no access to more browsers now. I will update this answer. But it would be good, if you can post some more experiences in the meanwhile ;-)
Comment of @Kevin B:
Definitely suggest cross-browser/os testing this before running with it, i've had issues in the past with linking to images for example with an erroneous // instead of / in the path working in chrome but not firefox.