Originally Posted by
RobbieRunner
Huge dude sits right next to me. Rest of the cabin empty.
I look at him and say "Hey, there's plenty of room".
He says "Yea, but I'm supposed to sit in this seat. See, here's my seat assignment."
Sure enough, it was right next to me.
Left to its own devices, meaning you don't pre-select a seat or that's not an option - (like 15 years ago ?) - the 'system' will start to allocate seats from the middle of the cabin and progress outwards.
The system is not programed to reassign seats when, close to departure, the plane is essentially empty.