Egmont said:
This comes across as lecturing us and is in any case too harsh.
Yes, I know that my way looks "too harsh" for most of you, not italian people, and I apologies. Please forgive me, it's not my intention doing so. It's part of my italian heritage. To me, it look like a normal conversation. Plus, I apologies for my english, I'm improving it, day by day. But please, note that I wrote: "milions of illiterates in english language (like me)...", so I could say that I was "too harsh" with myself as well. 
Loob said:
Oh no it isn't; and thank you, but no, I won't.
JamesM said:
Sometimes it's the very "mistakes" that native speakers make that identify whether the person is fluent in the language or not.
Absolutely agree. It's exactly what I wrote, 2 hours ago, on my personal note about the ERROR of calling the NUMBER '0' like the LETTER 'O': If I want to look moreexpert and fluent in the common language, then I've to speak as locals do, doing the same ERRORS (and much less my own errors ).
But the point I'm interested in, is not whether "Oh" is a common way of speaking, because it is (sadly). Reading the number 0 as Oh is currently normal, it's common, so, please, don't answer me "I do it" or "Nobody here say "two-zero-two", we all already know it, thanks.
The point is that it's an error:
1. The fact that, currently, milions or bilions of english speakers use it, it doesn't mean that it's correct.
In other words: the fact that it sounds "clean" to your ears, it doesn't mean it's correct.
2. The fact that there is no ambiguity in using Oh instead of Zero on reading a phone number or a street number, it doesn't mean that it's the correct way.
A. Do you even call the LETTER 'B': "Eight", as it looks like the NUMBER 8? No, of course.
You don't read Z and 2 in the same way: "Two", only because they look similar. They are different characters, so they needs and they have different names.
B. 0 and O look the same, but they aren't! So, you cannot call them with the same name only because you can recognize them; You don't call your twins: Mary and Mary only because you can recognize them and there is no ambiguity. They aren't the same person, as 0 and O aren't the same character.
It's not a matter of English, it works in this way about every language in the world. It would sound stupid otherwise.
So, why do you read the number 0 as the letter O? For a very simple reason, a reason you don't need a phD to understand: the language evolves throughout the centuries, mainly because of no litterate people mistakes (also because of influences by other languages, because of new product, new technologies etc.). An error become more common, day by day, and after some years a big part of population repeat that error, so it's no longer seen as a heavy error; other years yet, and the biggest part of population (which historically is illiterate), repeat that "light" error, so, it's no longer seen as an error at all, but as a correct word. Than, the rule has changed. I'm not proud using errors invented by illiterate people.
"As Henry Higgins observed in Pygmallion, the best grammarians are often those who learned English in school as immigrants. Over time, language evolves or erodes and the rules change, which really means there are no authorities. I believe many changes are driven by relatively poorly educated personalities misusing words, which then become common usage. Someone once said, "C students rule the world."
Our mistakes evolve the language, it's the reason why in Italy we don't speak latin anymore, it's the reason why the current language rules are different from the past, in Italy, in UK, and in every other country in the world.
About "Oh", I see that we're at the point that the bigger part of the population use it, thinking that it's correct, because "there's no rule" (...). But, as I showed, it is an error, a symple error, still, an error.
It's possible that 100 years by now, there will be the same discussion on "Your" and "You're": the biggest part of the population will say: "There is no rule, I use it, everybody here use it, you can choose what you like, it's a matter of taste". And my soul will be angry once again.
Best regards to everybody. Buonanotte.
Paolo
