I don't know, it's not the first time Michael ommits characters in a word... maybe there's a reason. Pronouncing the t makes the duration of the word a tiny little bit longer and it can be that a shorter duration was wanted for making the line more fluent... It would not surprise me. Didn't Michael sing "Heal The Worl"? (wirl lol) On other ocasions I clearly heard him pronounce "world"... @ Chamife : excellent idea! I'ld offer you a beautiful smiley now but I'm on phone modus and it doesn't work... Op voorhand al cheers op onze goede verstandhouding

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As a linguist I can safely tell when someone is using a dialect and when someone is playing with languages sounds. The Cascio singer uses what appears to be MD's dialect.
Michael never did similar pronunciation to the Cascio singer. I am positive about that and I already elaborated my answer on a page 1700 or something. Music has nothing to do with someone's dialect.
When Michael plays with sounds you get something like "trrrr, tap tap, trrrr tapatap" in Remember The Time video while he's dancing. Or a beatbox as in Who Is It. Or hiccups, aows, hee-hees, gulps, yelps, cham-ons, dahs, hee-hees, tchikan atcha ooow as in TWYMMF, etc, etc. But MJ never used MD English characteristics, not to mention that the voice alone doesn't sound "orthodox" MJ's.
I'll give you an example, and fans from London can confirm, Londonians don't say "a bottle of water" but "a bo'l o' wo'a" . This is quite common phenomenon with Maryland's English.
Or if you prefer, to make it easier for you, in Westvlaams dialect, exactly the same phenomenon exists -ellision of consonants:
the standard Dutch "Wij gaan chokolade koeken maken" becomes in Western Flemish dialect: "We goon cho'ola koe'e ma'a".
MJ had never used such common dialectal characteristics, neither in his speeches, nor in his songs.
At one point MJ even uses the British pronunciation of the word "better". Despite that, he remains consistant and uses the standard pronunciation without elliding the "tt"s, whereas even in Britain the ellision is quite common.
p.s. In Heal The World, MJ pronounces the words without any dialectal influence. I don't recollect that he ellided the "d" at the end of the word, but even if he let's say did it, it is not a dialectal characteristics, but his own way of pronouncing it.