>>51971592Allow me to explain it in a way that is easy to understand.
Shift Mode:
When a Pokemon faints on the opponents team, the game will prompt you for the choice of switching out your current pokemon on the field for one in your party, or leaving it on the field, it also reveals what the opponent is going to send out next. This eliminates the need for prediction or the need to have defensive members of a team.
Set Mode:
When a Pokemon faints on the opponents team, the game will immediately have the opponent send in a new Pokemon, not giving you a choice. A side effect of this is you need to waste a turn to switch into something that could handle the opponent if the current one on the field isn't suited, giving the opponent a free shot. Due to skipping the choice, it also does not reveal the mon until it is sent out.
If you're still a "VGC champion" as you claim (if you are the same person), how in the sweet flying fuck did you not know this?