How effective are bodyweight exercises?

Body weight resistance training is a widely used aspect of resistance training. Additionally, the high intensity interval training movement has utilised body weight resistance training as key aspect to their training regime. However, where does it sit in terms of performance and strength and conditioning?
Bodyweight resistance training is the building block for strength training. Every key movement, i.e. squat, deadlift, lunge, push up and pull up needs to be first mastered at body weight prior to adding load.
So what does mastery look like? The Australian Strength and Conditioning Association has in place some guidelines around this, but I personally like to simplify it. Can the key movements be performed safely and can the lifter perform these with as close as possible to perfect technique? In other words, ensuring correct muscles are utilised and body parts are in safe position throughout the course of the movement.
If these key criteria are met then the progression to load should be a natural one. Again, when load is added the criteria should not change, i.e. safe movement and correct muscle utilisation throughout. If we are able to add load to the movement we are triggering our system to overload and therefore gaining additional benefits. Therefore, the goal from a strength training point of view is to get to a point to add load. The stronger you become the more you can tolerate the impact your sport requires.
Bodyweight training also has an additional use, to assist with stability. Bridges, planks, single leg deadlifts and lunges are all examples of prehab, core strength or balanced based exercises to assist with performance. These exercises should remain a consistent part of any strength and conditioning program as an injury prevention activity.
To summarise, start general bodyweight training to master form then progress to adding load to the exercise. Make stability exercises a consistent and ongoing part of a strength and conditioning program.