Roger has it right.
However, what's missing is that Formula racers rig so that they are FULLY powered for deep down wind runs, which means that they are very overpowerd on reaches and a little overpowerd upwind.
Since a Formula race course is normally up wind and down wind, they rig big. That's why they wipe out on reaches.
On some of those crazy reaches Roger speaks about, I have gone to the chicken strap and luff the sail A LOT trying to make it to the finish line.