I am pretty sure I know the answer to this question, but I see mistakes reagrding it in both amateur and professional writing. I am wondering if any of you out there can give me your input about the following:

Commas in compound complex sentences.

I know how to correct two independent clauses with a coordinating conjunction:
It is raining, so I will bring my umbrella.

I know how to join dependent and independent clauses:
Because it is raining, I will bring my umbrella.
I will bring my umbrella because it is raining.

What about combining these rules?

I am going to the store, so, because it is raining, I will bring my umbrella.
or, perhaps more common,
There is no way to know if it will rain, so, before we plan to invite all our neighbors over for a barbeque, let's clean up the kitchen and living room as a backup plan.

I know you can just turn it around:
I am going to he store, so I will bring my umbrella because it is raining.

However, I do some nonfiction writing, and I like to vary my sentences often. I have also used commas this way in academic papers at the graduate level, and I have never received negative feedback about it. I know that this kind of construction could lead to run-ons, but I think the comma is necessary in responsible writing usage.

Are all people out there doing the opposite wrong? I often see the following:
We had a barbeque, and since it was raining, everyone had to eat inside. (Why no comma before "since"?!)

Does anyone have any opinions or ideas about this? Thank you in advance.

Hi Sarah,
Remember this fundamental rule of punctuation: It is there to help your reader navigate your sentence.

Many people omit the comma before the conjunction when one (or both) of the independent clauses are short. I brushed me teeth, and I went to bed. The comma before "and" doesn't add much. The reader can navigate on her own. I try to remember to always include it because "I was taught that way" but when editing other people's work, it's probably not an edit I would bother to make for such short passages.

When you join your clauses up as you have, you'd have "barbecue, and, since... raining," -- a pretty high comma:word ratio, which can look "fussy." Rather than helping your reader navigate smoothly, it feel more like when it did when you first learned to drive with a manual transmission: lurch, pop, lurch, pop, lurch...

The comma you refer to is correct, but not helpful, and therefore a prime candidate for deletion. (One of the rules of the comma that one of my teacher taught me was "When in doubt, leave it out." This was after she had handed back a paper telling me that it felt as though I'd opened a fresh box of commas and felt the need to sprinkle them generously throughout the paper. Few of them were wrong, but many were unnecessary.)

On the other hand, if you want the reader to pause there -- if you were transcribing how someone said it, and there was a pause, for example -- then by all means, leave it in.

So much of punctuation is style, not a matter of being "correct" or "incorrect." That said, some style guides are quite rigid. (I always put a comma after the state name or year in a full date in running text, even though those probably don't help the reader navigate either. Some habits are too ingrained to break.)
Does it only look "fussy" to people who do not know the rules (or have been reading so many incorrectly punctuated sentences that they don't know how to read a correctly punctuated one)? I have taught freshmen composition, and many students have no idea what a clause is, let alone how to effectively punctuate a complex and/or compound sentence.

I agree that it is a style issue, so perhaps my real question is the following: are we, in the sense of American writers, now compromising our style in order to please the uneducated masses? This probably sounds a bit cynical, but I think that, with the internet and its opening doors to publishing that might not otherwise be opened, we are losing stylistic opportunities that, to the uninitiated, seem "fussy" or "lurch, pop, lurch, pop."

I honestly don't think that a comma requires a "stop" or a "pause" that is very intrusive. I think that they are essential in conveying complex trains-of-thought. Maybe its a matter of losing critical thinking skills?