In a sequential motorcycle gearbox, why are the dog clutches on the sides of the gears back-cut (undercut)?

1. To act as a built-in torque limiter during crash situations
2. To create an axial force that pulls the gears tighter together when torque is applied
3. To reduce the weight of the gear clusters and improve throttle response
4. To allow gears to slide more easily into neutral when the bike is moving