TC3 Over years of lurking at various discussion forums, I've seen many variations of the following exchange:
Q: "I want to learn piano, but not classical piano. I have no interest in classical piano, I just want to learn [insert non-classical genre here] piano. Any advice?"
A: "Spend years learning classical piano first ... "
I am late at the party, but this reminds me on some of my friends visiting another school that teached latin:
Me: "Why do you learn latin? This language is dead, is it?"
Her: "If you speak latin, you learn other languges faster"
Me: "If I want to learn italian, why not go for italian directly?"
Her: "Knowing latin helps you to understand italian way better."
Me: "How does this work?"
Her: "Italian evolved out of latin. And latin is more complex, so it gives you the best theory underground."
Me: "Isn't it enough to know only complexity of italian?"
Her: "But then you don't understand the language."
Me: "So the average Italian does not understand his mother language?"
Her: "You don't understand... "
Me: "Okay, how much time do I safe learning italian, if I know latin beforehand?"
Her: "One or two years, probably"
Me: "How long does it take to learn latin?"
Her: "About five."
Me: "Okay... but then the total time is"
Her: "Shut up! "
This "start with classical" is very similar in my opinion. The only fair point I can see, is how music evolved. Classical is the oldest genre (if I count hymns and chorals to classical). This means, all the people of that time period have learned classical music without another music genre as educational background. And this is the ultimate proof you can start with classical music from the scratch.
And music schools are doing this for centuries (and it works, obviously).
This means all young kids sent to a music school are starting with classical music. And some of them are becoming great musicians. Some of them even the best musicians out there.
And this is why you will always hear the same argument: "Start with classical, because the best musicians started with classical, too."