Training for Endurance
This video by Tom Randall of Lattice Training talks about the 3 common mistakes when it comes to training for power endurance.
If you are training for climbing outdoor then train like how you climb outdoor. Slow down your climbing pace when you are training in the gym. Stay on each handhold and foothold longer to simulate how you climb when you are on an onsight attempt.
When training for a specific project you should focus on climbing routes with the type of holds and grip position that are found on your project route. This will maximize your training session specifically for your project.
Different projects requires different climbing style. It is necessary to train on climbing movements that are specific to your project. Identify the most efficient movements needed to send your project and train on those specific moves.