User blog comment:Robbylet2/English tip of the day part 2/@comment-24002826-20150617045612

Incorrect. Starting a sentence with "and" or "but" is grammatically acceptable according to numerous sources. It's more of a stylistic thing, but there' nothing inherently wrong with it.

I do it primarily to make the phrases more conversational, but I will admit that I may have overdone it in previous years.