I agree with ToiletDuck that this is more a safety issue. It should be analyzed as a safety issue or it'll just get moved to the back burner. As a passenger, I detest sitting next to a large sized person with his/her sweaty fat arms and thighs pressed tightly against mine for the entire 4 hour flight. If you are that fat, you probably should take your own car when you want to go somewhere. Don't force your lard on other innocent people.
I'm sure there will be a lot of chunky folks get all offended by my remarks, but it's time everyone take personal responsibility for themselves. Be cognizant that you have a problem and that there is a solution.
It would behoove airlines to establish a rule on this. Or get with Boeing to design something different.
Thread moved to Safety Forum.