Why I use commas the way I do

I get a lot of "commas don't go there!" when I write, but the majority of people who think I use too many commas are wrong.  Most people in America are taught to use a list like:

X, Y and Z
as compared to my
X, Y, and Z

My style of comma usage is the implementation of the serial (or Oxford) comma.  This is generally used in cases of ambiguity, or confusion, or aid prosody, or the rhythm and stress of reading.  I generally use the serial comma because I find it easier to read faster with the clearer separation in lists.  An example:

To my parents, Ayn Rand and God.

This particular book dedication presents ambiguity: is the author dedicating this book to her parents and Ayn Rand and God, or is she dedicating it to her parents, who are Ayn Rand and God?  The insertion of a serial comma, making it:

To my parents, Ayn Rand, and God.

Would clear the issue up.  There are issues of ambiguity when using serial commas in longer sentences, but generally that can be cleared up by splitting sentences or proper semicolon usage.