In XI(when we first started) my bro and I did this with 1 character. I was on during the morning to afternoon and he was on afternoon - night. The character was almost always on but people knew it wasn't botting because we always made our own parties and talked. That character became very popular and even made a group of JP friends. We would even let the other know anything that changed or any new person met so people would think we was just one person(our attitudes are the same also).
For this topic though it would be easy to say this person is botting but I don't know the person(or remember seeing) as he/she is even on my world to say it's a bot.