However, I would like to point out the narrow interpretation he makes of "standard English."
I value other forms of English, as I have made clear in other threads, and perhaps 'standard' is not the best expression for the forms I have mentioned above.
However, my experience of nine months in this forum suggess that most of the people writing in with questions are interested in what is generally considered acceptable in the not-too-informal language of moderately (at least) educated speakers of AmE and BrE and, possibly, CanE, AusE and NZE. With the international acceptance of such US, British and Australian examinations as TOEFL, CPE, CAE, FCE, IELTS, etc, this is not surprising; the past prestige of Britain and British writers, and the current military-industrial-entertainment power of the USA also contribute to these two dialects' position as market leaders. Where the interest of people asking and/or responding is in other dialects or registers, this is normally made clear.
250,000,000 hits for "ain't" does mean it is acceptable, in certain contexts. George W. Bush used it all the time, in public. I never do, because it's not standard in my region and sounds foreign to me. But no one, not even an Englishman, can dicate to people in other regions what is or isn't standard English.
I am not attempting to dictate anything to anybody, but I think you are being a little disingenuous here. (I don't think there are many people who would hold up Dubya as a model producer of 'good' English.)
"F***ing f*** off, ya f***ing f***er" is acceptable in certain contexts as an alternative to my, "With all due respect, I think you may be mistaken". I don't think it is particularly narrow of me to say that this is 'not acceptable in standard English.' Peope writing in to this forum need to know that, other than in certain dialects and registers, in fairly informal spoken exchanges and in certain fixed expressions such as 'If it ain't broke, don't fix it', learners are well advised not to use 'ain't'
I looked through our local newspapers and have noticed that they generally avoid both "the police are" and "the police is", sidestepping this issue entirely by using "police force", "police officers"... and so on.
We can't draw any real conclusions either way then, can we? Even if we could, we would be doing so only for the English used in the are covered by your local newspapers. As I wrote in an earlier post (accepting the reservation about my use of 'standard', and with emphasis added): "I still feel that in
most standard dialects, 'police' cannot , after the French style, be a singular collective - except when referring to the institution".