When emailing and texting, what do you think about the use of emoticons? I've heard a bunch of people say to never use them, and other people say they should only be used rarely, but I haven't heard much of any reasoning or fieldwork proof supporting this opinion.

In any community some ideas pop into being for no good reason and then take on a life of their own as people repeat that idea over and over again, reinforcing the believe that everyone "knows" that it's true, even though in actuality there's no proof or evidence that it's true, and may in reality actually be false. In other words...

TL;DR Does anyone have any significant amount of real field report experiences or other proof that emoticons are bad?