re: single or double-space, I bow to the Chicago Manual of Style - to wit:
"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."
Note:
follows the industry standard of one spaceAs to self-editing in general, I do everything as I go (edit/proofread/revise/rewrite); if it isn't the way I want it, I don't move on. Of course, one has to accept that perfection is impossible, and that there's a difference between improving it and just making it different. I'm also a huge fan of reading it out loud to catch problems (not some program reading it but ME reading it). I have tried to leave things for a while before final proofreading, but frankly, I know the story so thoroughly by the time I finish, even reading them months later is like listening to the same song for the 40k time - ie, unbearable. So I basically have to get it right the first time.

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