Andrés, I didn't mean to refer to the Tarzan way of yodeling: Simply shouting with breaking voice thus making your enemies believe you've got elephants (joke as far as I know invented by René Goscinny, God bless his soul).
I meant having your voice break and of course HIT THE TONE that is required. A song has its melody. There are no further musical restrictions (at least in folk music). That melody may be obtained by singing it with a male voice (tenor, baritone, bass, boy, castrato soprano) a female voice (soprano, alto, girl) a whole choir, even by playing it with a musical instrument or whistling it. Of course only if this is done IN TUNE. And when I mention yodeling I am of course referring to the musical kind of it: Yodeling some given melody.
With this breaking of the voice is only one of many different ways of performing a tune by means of the human voice, i.e. singing. That is why I'm a little biased to teachers as I said. I am convinced that they can tell me many things I don't know but also that they will first try to restrict me to THEIR things. So I suppose we would first quarrel instead of talking about singing and that is not what I think teaching/learning should be.