replace emphasis with quotes so that emphasized "a" isn't misunderstood as an article.

Usually such emphasis means it's being used as a variable name or symbol.
When stripping markup, replace unresolvable templates with placeholder __

That way, when a template is after a/an, the word following the template isn't
misunderstood as the word affecting the article.
No need to strip emphasis; that's being converted to quotes already.
Update default regex options; always ignore pattern whitespace.
Tweak simplification, allow occurence == scaleFactor
When stripping html tags, really only strip html tags and not just any old <> pair
Unfortunately, wikipedia contains html-esque tags that are content, not markup.
Add comments regarding what to pay attention to when finding the word following a/an.