So I am fat. Big deal. I sit in my own seat and have hardly ever invonvenienced another flyer.
Unfortunately I cannot say that I have received the same consideration. If a person is going to selfish or rude then size does not matter in the slightest.
- I have sat in aisle seat with a tiny female in middle seat who thought it was her God given right to both armrests
- I have sat in aisle seat with a male in middle seat reading a Herald/Australian newspaper with fully stretched hands
- I have sat in aisle seat with "big" male in middle seat. Not fat but very broad shoulders and sat back for the entire flight. It meant that I had to lean forward as his shoulder was taking up where my shoulder would have rested
- I have sat in aisle seat where person in middle seat leans on the armrest between us to give person in window seat more room. So why choke me?
And then let's not get started on the other flithy habits people bring with them out in public....
I'm 188cm tall, I have broad shoulders and an expanding stomach

However I keep to my seat and I don't encroach on my neighbour.
/sarcasm
I've had a few experiences with petite females who have an unfortunate medical condition where their elbows seem to be stuck like chicken wings. This causes them to require both arm rests.
/end sarcasm