Help me do the comma

[Pyrrho]

Fine links, but you are wrong in your statement:

http://www.mla.org/style/style_faq/mlastyle_spaces

Double spaces after a period (or other sentence-ending punctuation) is traditional, and the way I normally type.

Tradition is irrelevant, but you should look for the reason behind the tradition. Double spacing was used with uneven font types to make them look more uniform. That is, to make it look like they only had one space between sentences. Also, this:
http://www.chicagomanualofstyle.org/qand...orTwo.html

From your link:

Q. Help. How many spaces do you leave after a colon in a manuscript?

A. One space after a colon. There is a traditional American typing practice, favored by some, of leaving two spaces after colons and periods. This practice is discouraged by the University of Chicago Press, especially for formally published works and the manuscripts from which they are published.


Q. Please help. I have confusion regarding the correct spacing after periods and other closing punctuation. My company uses the font Arial and consistently uses a flush-left margin. We are an engineering company. My job consists in preparing documents and letters for customers. Everything I read in manuals and from technical writers directs me to use one space after periods. I find that it works very well, except occasionally, when an extra space helps readability. Knowledgeable engineers have embraced the one space use as being consistent with the font design and automation of reports. Others are unpleased with the one space, they think they have difficulty reading. (I, too, had an adjustment period which I forced myself to endure until it became automatic to read easily.) We are preparing technical information. What do you think? Thanks for your wonderful support and especially the quick answers. I greatly appreciate your service.

A. Published work these days rarely features two spaces after a period. In the era when type was set by hand, it was common to use extra space (sometimes quite a bit of it) after periods, a practice that continued into the first half of the twentieth century. And many people were taught to use that extra space in typing class. But introducing two spaces after a sentence-ending period—and only after those periods—causes problems. Absolute consistency is easy to monitor when double spaces are never allowed, but less easy when some spaces after periods are double and others single (such as those at the ends of abbreviations and initialisms in running text). Since there is no proof that an extra space actually improves readability—as your comment suggests, it’s probably just a matter of familiarity—CMOS follows the industry standard of one space after a period.

http://www.chicagomanualofstyle.org/qand...orTwo.html

Your source doesn't say that it is wrong to have two spaces.  They merely favor one space.  No one said one space was wrong. But it is wrong to say that two spaces is always wrong.  And your source is good enough that they don't claim what you seem to imagine that they claim. 


In other words, you are wrong to tell people that using two spaces in such situations is wrong.  It is not wrong, and neither the CMS nor the MLA say it is wrong, because they are decent sources.


For those who need it, here is the MLA on this:

http://www.mla.org/style/style_faq/mlastyle_spaces