I think all the antidisirregardlessnessificationists should brighten up and see the funny side.

Some originally redundant features are obligatory in standard English. Did you know the -ren in children was originally two plural markers stitched together? The Middle English plural of child was childre / childer (compare German Kind and Kinder). When the -re plural suffix became rare, childre became children by analogy with brethren. But the second R in brethren was actually part of the singular stem, brether (brother); the plural suffix of this word was -en, not -ren. You could call it a mistaken analogy, but there's no alternative in modern English. Nowadays, if someone says childer, they usually think they're saying singular child in 'Ye Olde Englishe'.

@Dude: some people do say, "I didn't sell nothing today." It's inappropriate in formal standard English, but it's very common in many dialects. Although by formal logic someone who says this is saying, "I did sell something," pragmatically they are normally understood as saying, "I sold nothing." Evidently, natural language isn't based solely on formal logic.

Most native English speakers probably don't actually care, but I'll point out that the word "irregardless" has been accepted as "wrong" enough (at least in "standard" English) that the usage of the word was actually one of the jokes in the 2004 movie "Mean Girls": https://youtu.be/X34Jo5OAJ6s?t=18. Basically, a character who is generally portrayed as dim uses the word, and her usage of the word highlights her dimness.

Of course, plenty of linguists and those who don't believe in prescriptivist language took issue with this:

I tend agree that whether something is a "real word" is just a function of time and place. However, if using the word is widely recognized as a joke in the move... it does say something about how the common population might think about you using the word. Whether the common opinion is right or wrong is another discussion.

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Take 2 (after I thought about it a bit more):

The point of verbal language is to communicate. If we accept the point of language is to communicate, then the whole debate about a word being "right" or "wrong" or "real" is moot if the communication has happened.

That said, since time immemorial, the communication that occurs is not restricted to the literal meaning of the words themselves. Your choice of words communicates something as well. It communicates your social group / class, your attitudes toward "formal" or "proper" top-down English, and so on and so forth. For example, it's been pointed out many times in the discussion that "ain't" is commonly accepted in some places as slang, and even though I have no issues with other people saying it, if I said it within my given social group it would definitely raise eyebrows. Same with "irregardless". Alternatively, certain writers are criticized by the general population for being "pompous" because they use vocabulary that's "too flowery".

Unless we bestow some magical authority to the people who happen to work at dictionary companies, whether or not your manner of speaking is "correct" is dependant on which social group is judging you. In "formal" contexts, I suppose that social group is what we might call the top-down "cultural elite": in essence, it's whatever the government and the educational system has decided is correct.

But in day to day life? Then it's context-dependent.

It's one of many phony issues in English. People divide into factions and like to be correcter-than-thou. This is an interesting example, because I have certainly heard it used, commonly used, by educated speakers, since my childhood in the 1950s.

It falls into the category of things that you shouldn't use, because whether or not it is right, people think it isn't and will yell at you.

However, I admit that the American Heritage Dictionary is strongly against it:

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ir·re·gard·less

adv. Nonstandard: Regardless.

Usage Note: Irregardless is a word that many people mistakenly believe to be correct in formal style, when in fact it is used chiefly in nonstandard speech or casual writing. The word was coined in the United States in the early 1900s, presumably from a blend of irrespective and regardless. Many critics have complained that it is a redundancy, the negative prefix ir- duplicating the negativity of the -less suffix. Perhaps its reputation as a blend of ill-fitting parts has caused some to insist that it is a "nonword," a charge they would not think of leveling at a nonstandard word with a longer history, such as ain't. Since people use irregardless, it is undoubtedly a word in the broader sense of the language, but it has never been accepted in Standard English and is virtually always changed by copyeditors to regardless. The Usage Panel has roundly disapproved of its use since polling began; in 2012, 90 percent found the sentence A scientist investigating a social issue should seek to find out the truth, irregardless of its political implications to be unacceptable."

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However, they don't deal with the most common use, as a way of adding emphasis when "regardless" is being use almost as an interjection. For example, "They said a vegetarian restaurant would never succeed in that town, but they went ahead and did it, irregardless."

"irregardless" doesn't sound bad because the root itself (regard) doesn't convey a strong meaning. It's old-fashioned and often found in formal salutations and the like. People don't "calculate" the meaning of either 'regardless' or 'irregardless' - so one is as good as the other. Personally, I like brevity and do not add the "ir", though. I can imagine it evolving into a slightly emphasized version of "regardless" - perhaps it already has that connotation.

Dude:

I understand the point you’re trying to make, but “I didn’t sell nothing” is perfectly correct non-standard English. Quite a few dialects use double negatives.