You're right Ron , there is a huge amount on the subject of P factor, Gyroscopic precession, spiral slipstream and torque effects.
Logically P factor must always have an effect anytime the prop disc is at an angle to the airflow. How much effect that has on the aircraft must depend on what other forces are acting at the time.
For a tail dragger at take-off I would imagine that gaining forward speed as quickly as possible without tipping the nose would be the way to reduce the yaw effect.
For a trike, by the time the nose is raise you already have a reasonable air speed so P factor and spiral slipstream effects are already reduced relative to the aerodynamic forces provided by the wings, tail plane and fin.
A question for the experts: What effect does P factor etc have when doing a stall turn?