Pursuit curves describe where you point your aircraft relative to the bandit.You will often point your lift vector instead of the aircraft nose.
Lead Pursuit points ahead of the bandit's current flight path. This is used for maneuvering and is often required for shooting to allow for time of flight of your shots.
Lead pursuit is used in maneuvering to intersect the bandit's flight path. This can get you closer to the bandit and can set up a snap shot as the bandit passes in front of you, or you can transition to lag pursuit when you have closed to your desired distance.
Lead pursuit can lead to too tight a turn and leave you too slow. Mind your speed.
Pure pursuit points at the bandit. Like lead pursuit it can reduce distance to the bandit but not as quickly. Pure pursuit is mostly used in head on attacks and in the tail chase.
Lag pursuit points behind the bandit. Lag helps you align flight paths to put you in the control position behind the bandit.
Lag pursuit maintains or increases the distance to the bandit.
Excessive lag pursuit can allow the bandit turning room to gain angles for a shot. Watch the bandit and assess your plan.