Why is there a persistent tendency...

Where exactly is the grammatical rule that bans using words like okay to start a sentence. Would they apply to using a more "churched up" application like starting a sentence with the word alright?
 
It's not so much a rule... at least as far as I know... - just bad form. What is a rule, is that elipses (...) are used in place of words that have been removed from a quote. They are not supposed to be used to indicate a trailing thought. I break that one all the time...
 
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