Also, I have one writer friend who had to go through the last book she sold to do what she said was the 'great comma-ectomy' ... removing about two commas out of every three, the way she used to write. Do you find that you are using fewer commas now? I do think a lot of writers use too many commas, but still -- they really aren't incorrect -- just bothersome. What's your opinion here?
My personal experience is that I am not using more or fewer commas, but rather that I'm more conscious of when, how and why I use them.
While looking for a way to explain, I went to my bookshelf — actual as opposed to virtual — and read up on what fellow instructor Harvey Stanbrough tells writers in his book Punctuation for Writers: A Thorough Primer for Writers of Fiction & Essays.
I highly encourage you to buy the book, since he covers the subject so thoroughly, as the title suggests. But a basic concept he puts forth is that punctuation consists of symbols that tell readers where to pause and for how long. If you want readers to take a decisive and significant pause, you use a period. If you want a short pause, you use a comma.
Therefore, when moving through your manuscript, consider how often you want readers to pause and for how long. The decision will greatly affect the style of your writing.
1. Few commas within long sentences create a style of someone running off at the mouth: "Susie told me she likes Hal but I know better than to trust Susie because on five occasions she's lied to me and every time it hurts which I didn't expect considering I don't like or respect Susie.
2. Few commas within short sentences create a staccato feel as readers read-stop-read-stop: "He turned. I looked at him. He didn't have to say anything. He pulled the door closed behind him."
3. Many commas within a short sentence ask readers to go this way then that way and now this way again: "She, too, I think, would, if given the chance, succeed, though maybe not."
4. Many commas within longer sentences creates a long rolling feel, like that of a cruise ship in high seas: "Had I known what I do now, I would never have exposed Marge to the likes of Mr. Anthony Frinolli of the Superior Shipping Company, and so started her on a course in which she soon lost control."
The point is to make a conscious decision about what punctuation you're using, how often you're using it and what effect that usage will have on the style of writing and the clarity of the storytelling.
In terms of other types of punctuation — semicolons, colons, em dashes, etc. — the fewer you use, the better, since the symbols make the sentence more visually complex. That and most readers are unsure of how to interpret them.
I am but one voice in the universe, however, so continue to consult various resources until you find the advice you understand best:
• Guidelines for Using Commas
• The Comma — Part I and Part II
If you have advice to offer on the subject, please do.