The problem I had the most with the list was that it's called a thin privilege checklist and I take thin to mean something similar to skinny rather than "average". The dictionary seems to agree with me. That general problem mentioned, I have some more specific things to say about specific items on the list.
People won’t ask me why I don’t change the size of my body.A close friend (and ex-boyfriend, if it matters) of mine is naturally what many people would call "very skinny". The number of times I've heard people ask him why he doesn't gain weight is not insignificant. The number of times he's been asked that is probably similar to the number of times I've been asked why I don't lose weight. I somehow doubt that this is unusual for people on the "very skinny" end of things, and as such have trouble accepting this as a marker of thin privilege. Beyond that we live in a society that seems to believe that unless you poses the ideal body (and no one does) you will be asked why you don't change this that or the other thing about your body, so I'm not sure anyone gets away from this regardless of their size.
I am not identified by the size of my body.Anyone whose body is non-average in any way at all gets identified by the size or shape of their body. The friend mentioned above is generally described as "skinny with a beard", another male friend who is 7 feet tall is "the really tall guy", and some of my female friends are described by people who don't know them based on the fact that they have rather large cup sizes and not so large anything else. This is a somewhat obnoxious thing, and I'm not sure that "skinny guy" is the same sort of identifier as "fat girl", but it's certainly not an experience that is unique or even significantly more common among fat people.
I am not grouped because of the size of my body.I'm pretty sure everyone is grouped because of the size of their body. That's the sort of category that we're used to grouping people by. Again, obnoxious but not just something fat people deal with. I would suggest that maybe fat people get a negative connotation along with their group that is unique to that grouping, and that there being less value judgement given to members of other groups is a mark of privilege for those other groups, but the grouping itself isn't.
I will not be accused of being emotionally troubled or in psychological denial because of the size of my body.Women who are naturally very thin get called anorexic with very irritating frequency. Perhaps if you fit in the window of "average" this isn't a problem you face, but people who are fat and people who are thin both get this sort of accusation. It is wrong and a very bad thing, but not a marker of thin privilege but a marker of average size privilege.
My masculinity or femininity will not be challenged because of the size of my body.Men who are very thin are often considered "too feminine".
While I definitely am bothered the "but skinny people have it bad too!!!" argument that comes up pretty much any time you try to have a discussion about being fat in any forum on the internet, I felt that if we were making a list about thin privilege we should probably make sure the problems being discussed aren't problems that thin people also have. Much of this issue would be fixed by simply calling it an "average sized person privilege" list, as was done here, and perhaps some of my issues here are really just me being pedantic. However there is one item on the list that list that I strongly believe doesn't belong on any size privilege list.
I can go for months without thinking about or being spoken to about the size of my body.If you can do that, then I'm pretty sure you live in an entirely different world than I do. Sure, people who are "average size" are probably spoken to about the size of their bodies less often than thin people who are probably spoken to about the size of their bodies less often than fat people, but I get the feeling everyone is spoken to about the size of their body occasionally, especially if they're a woman. Beyond that, I'm unsure how anyone (especially women, and at least in modern American society) can possibly go for month singular much less months plural without thinking about the size of their body. We are constantly bombarded with images of excessively photoshoped "perfect" people, magazines that tell us how to make our bodies look like whatever they aren't, and ads for diet products that suggest that everything would be better if you just lost 10 lbs. You don't have to be fat for these things to make you think about the size of your body. Beyond that, you have to put on clothes sometimes, sit in chairs sometimes, exist around different sizes of people sometimes, and generally live inside your body. Maybe it's the eating disorder thing, but all of those things sometimes make me think about the size of my body. Sure, it's likely that not everyone thinks about the size of their body with the frequency that I do, but going for months without thinking about the size of your body seems to be in the realm of hyperbole to me.
Basically, my suggestion here is that we maybe talk less about "thin privilege" and more about "average size privilege" and remember that the whole society we live in lends itself to an obsession with body size regardless of what size your body happens to be.