Donna Pattee wrote:

> In article >,
> PENMART01 > wrote:
>
>>"Julia Altshuler" wrote:
>>
>>>First, don't be put off by getting a basic cookbook. Everyone has to
>>>start somewhere,* and you'll be a happier cook in the long run if you
>>>learn the basics well and build from there.
>>>
>>>Second, you'll find more potato recipes on the web if you spell it
>>>P-O-T-A-T-O. (I'm not normally one to go around correcting spelling,*
>>>but in this case,* it makes a difference in achieving your goal.)
>>
>>Commas are not decorations, nor are parentheses.
>>I know, you're an obsessive-compulsive punctuator and/or a hesitant speaker.
>>
> The first of the two commas you flagged were used correctly.

The first of the two commas you flagged *was* used correctly.

> The third
> comma was not necessary.

If the rule being applied is "when a conjunction connects two clauses
that could stand alone as separate sentences, then a comma precedes
it," the sentence doesn't need the second comma.

But it may also be correctly punctuated, "I'm not normally one to go
around correcting spelling but, in this case, it makes a difference in
achieving your goal." A non-essential phrase should be set off by
commas. And a serious pedant would even put another comma in front of
the "but" so it reads "...spelling, but, in this case, it makes..."

Dueling rules...

> One way to tell if a comma is needed is to try
> the parts of the sentence as separate sentences. Doing this you will see
> that both "Everyone has to start somewhere." and "You'll be a happier cook
> in the long run if you learn the basics well and build from there." stand
> alone as proper sentences. Thus, putting them together with "and" means
> that a comma is required.

The rule is that the comma is to be used with a conjunction in a
compound sentence when punctuation is necessary for clarity.
Otherwise, it may be omitted and generally should be. The sentence
quoted here doesn't need it to be properly understood.

Pastorio