I agree with Beach Patrol. I've been criticised for joking about my weight, but I don't see it as any different than anyone joking about their personal attributes or quirks. I DON'T equate fat with with lazy, crazy, or stupid. I don't equate fat with ugliness or even with an obligation to change. I've also used the word fat*** (butt) to refer to my large posterior. I don't use it to bash myself, because I don't see fat as anything deserving of any type of bashing.
My a** IS fat. So are my fingers, my arms, my legs, my feet, my stomach. My head ironically isn't (and I don't just mean that literally). My mom always wanted me in hairstyles that were short, close to the head because it made my face look thinner. I hated it even then, because it made me look like a pinhead (no offense meant to actual pinheads). Full hair gave my face a more proportional look, so as soon as I was fully responsible for my own hair, I wore it in fuller styles, because I hated looking like a football player or like I had a shrunken head.
Being fat can be miserable, but there are funny aspects of it. Self-deprecating humor really only works if you've got real confidence. I can make fun of all or any of my imperfections because I know how truly fabulous I am.
Everyone has an a** and mine just happens to be fat, so I have absolutely no problem with making reference to the actual size of my a** and where said fata** won't fit.
I actually have used the words fat in reference to other people and their fat body parts, (though only with those like myself who don't see it as an insult).
I wouldn't use it as an insult (because it should have no power to insult) and I don't use it with anyone who doesn't KNOW and BELIEVE that it doesn't have to be an insult.
The only way fat will ever become a neutral word is for people to use it neutrally and stop using it as an insult. I use the word as I believe it should be used as often as I can, and explain my reasoning when I do.
Not everyone agrees with me, and people will vote their beliefs with the words they choose to use. I just hope fluffy never becomes the word of choice. It makes me think I need to put some of my hair in a bow or barrette at the top of my head, like a long-haired lap dog.