By the way, at least one authority backs up my intuition that the
protocol should be usually omitted: The Modern Language Association.
According to the MLA Handbook, URLs should always remove the "http://";.
Excerpt from style.mla.org/urls-some-practical-advice/
MLA's Guidelines on Truncating
“The MLA Handbook advises writers to truncate a URL in one specific way
(by omitting the protocol and //). If you need to shorten it further,
retain the host, which will allow readers to evaluate the site and
search for the source.”
The MLA Handbook also has a useful example of how a professionally
typeset publication might break URLs across lines.
MLA's Guidelines on Breaking
“To ensure that a URL is accurately reproduced, never introduce a
hyphen or space in it. Note that the freely available formatting
guidelines on this site advise writers to turn off their word
processors’ automatic hyphenation features for just this reason.
Professionally typeset publications in fixed formats, like print or
PDF, normally follow rigorous conventions for breaking URLs.
Publishers vary in their practices. In its own professionally typeset
publications, the MLA breaks URLs before a period and before or after
any other punctuation or symbol (e.g., /, //, _, @). We do not break
URLs after a hyphen in such publications, to avoid ambiguity.”
In comparison, the current implementation in groff's WWW packages is
lacking:
* it currently only breaks after slashes but should do so around any symbol,
* periods should break before but not after, (likewise percent, imho),
* it should disable hyphenation of words,
* text runs off the right margin if the URL has a long string of consonants,
* a URL that is longer than a single line should begin on a new line,
—b9
