I'm sure the other thread insisted that up was behind. That's not the way I learnt it, and it's very confusing if you accept it. As I said at the time, imagine a road race, where up is definitely ahead.
So, the rider up the road passes the car that's down, which then passes the bunch and goes up, before passing the riders who are down.
Nah. Ahead is up both in racing and in general bunch riding.