I take the middle aisle in the hopes that if someone's stuck in the middle seat, they'll bug the guy on the other side when they have to get out.

Assuming all full, if it's 3 middle seats, it's probably a crapshoot as to who they'll bother. If it's 4 middle seats, then the middle-left will bother the person on the left, and the middle-right will bother the person on the right. Hopefully.