This is not a duplicate of earlier questions asking whether or why the comma splice is an error, because I am asking about the debate itself: unlike many another grammar rule that is widely accepted by all parties, why are so many people on opposite sides when it comes to the comma splice?
I see comma splices every day in very well written members' comments on multiple Stack Exchange sites and also in so many articles on the World Wide Web. My mind keeps identifying the comma splice and suggests the semicolon as a possible alternative. With such widespread use the comma splice seems to have gained descriptive legitimacy. I sometimes use comma splice myself and only recently learned that some grammarians consider it an 'error.'
Looking back over the previous questions about comma splice I came across this relatively recent question:
Why is the comma splice an error?
And I was surprised to see I had already posted this comment:
It seems that comma splice is now considered legitimate. Many members here use it regularly in comments and some even in answers; and at least one senior member (I forget who because it was 2 months back when I was new here) advised me outright that comma splice is preferable to semicolon in modern English writing. – English Student Jul 15 at 1:43
To which another member responded,
incorrect usage by senior members does not justify it. It is still incorrect usage, although comment sections are hardly the best example of a context where proper use plays an important role. In formal writing, the comma splice ought to be avoided. – Octopus Jul 15 at 3:09
There definitely exists a wider grammatical debate beyond this website about the appropriateness of the comma splice.
From “Grammar Tips” a website run by Tina Blue, lecturer and author of several articles, who affirms
The fact is, though, that in the U.S. a lot of people who are sure they understand the "rules" of English firmly believe that all comma splices are not just errors, but really big errors, and that any one who commits a comma splice is demonstrating a fundamental inability to control a sentence. If I were to use a perfectly acceptable comma splice, I can be sure that an awful lot of people would assume that I have no mastery of sentence boundaries. […]
Sometimes it seems that the rule against comma splices is the only rule that many people –English teachers especially!– have managed to master, and so they are always on the hunt for an opportunity to wield it against someone. (link) While it is true that in American usage most comma splices are errors, it is also true that some are worse errors than others, and some are not errors at all. I am not even sure it is considered a matter of concern in British usage [...]
On the other hand, from the Economist blog article rather hyperbolically titled "The dreaded comma splice":
SEVERAL months ago I was surprised to see Arnold Zwicky, a linguist, use a comma splice. A few commenters took me to task for being over-picky. The question came up again in the comments several days ago, when k.a.gardner, a frequent commenter, asked for a post on the comma splice. One of my colleagues quickly replied that "The comma-splice rule is totally arbitrary," and a back-and-forth ensued.
What is a comma splice? Prof Zwicky wrote back in July
"this is not even a tempest in a teapot, it's a fuss in a thimbleful of spit."
That's two independent clauses joined only by a comma, or a comma splice [...]
Is there any more doubt that an established debate exists with strong and entrenched views on either side? It is not even an opinion based but a grammar-based debate. And I want to know why.
The C-clamp and the notorious sandwich:
In a closely related article Tina Blue goes on to say:
Barbara Wallraff, who writes the delightful "Word Court" column on the back page of The Atlantic Monthly, has recently published a book on the correct use of language. [...] The current Quality Paperback Book catalogue quotes from her a wonderful line about comma splices--
"Take this sentence, for example: 'It's not a comet, it's a meteor.' According to Wallraff, 'punctuating this sentence with a semicolon would be like using a C-clamp to hold a sandwich together.' "
Precisely!
There are times when a comma splice is a justifiable stylistic device, not an error.
So is it really a matter of style?
if large numbers of well educated English writers are using comma splices as well-considered stylistic alternatives to semicolons and conjunctions (both of which they may consider outdated and excessive), how long can some grammarians continue to deem it a to-be-avoided error?
Conclusion:
Of course I am no grammarian myself, but this is a query as to WHY there is still a grammatical debate rather than consensus over the comma splice. Why does the comma splice elicit such marked disagreement when many another grammar rule has been widely accepted by all parties?
Specifically, what stylistic or grammatical reasons prevent users and grammarians from reaching a consensus on the issue?
Many thanks to @Edwin Ashworth for updating his comprehensive answer on the original question and introducing us to the excellent articles of Tina Blue.
Note to members: I welcome adequate references to ensure that your answers are not read by others as 'primarily opinion based.'