From Facebook: The Smaller Hooligan's Godmother posted:
Okay all you people who think you're so smart for knowing your vs. you're and their vs. they're: Click "Like" if you know what an appositive is and when it requires a comma.
ps I may have to blog some of this, but I will get your approval before anything hits the infernal net.
She wrote back right away. She is prompt, or perhaps I should say punctual (English Major joke).
Just today I was writing a sentence like you describe. I left the parenthetical remark unpunctuated, although it was technically a complete sentence and occurred in the middle of another sentence. Punctuation is just annoying in the middle of a sentence (even when the parenthetical is a complete sentence), and annoyance should be avoided at all costs. The only exception I can think of would be if the parenthetical was a question (And who doesn't love questions?) because they require the question mark to indicate tone. Then I'd capitalize it and include a question mark.
When it's at the end of a sentence, it's much easier to deal with. You can simply punctuate the parenthetical like a complete sentence, like this:
I find this particularly troubling when I parenthetize at the end of the sentence. (I did this in the final paragraph of my last post, quite frankly.)
Of course the actual parenthetical you used:
(as I did in the final paragraph of my last post)is not in fact a complete sentence and therefore would not require punctuation.
I hope this makes sense! Rules of punctation vary from style guide to style guide (AP Style is often different from Chicago Manual of Style) and are, frankly, a matter of taste. I go for maximum clarity whenever discrepancies arise.
This is a woman who knows about style, literary and otherwise.