techniques: ghetto jump
Pure height technique, done by L jumping against a specific nearby object to reach something a standard jump wouldn't. The object used is different in every room, but it's usually a wall or uneven ground.
Get a running start and L jump against an object just as you touch it. Move away from the object immediately after pressing B. The reason for this is that most objects have a certain point in height where you can no longer be pressing against them, otherwise you'll be dragged back down.
Notes:
- In some places, it's actually better to stay pressed against an object. It just depends on what's being used for the jump, because everything affects your jump differently.