In editions of Dungeons & Dragons up to and including AD&D 2E, each class has its own progression rate, so that at 3,000 XP you could have a level 2 fighter, or a level 3 thief. In 3E, 4E, and 5E, there is a single rate of progression for every class. In 3E, 3,000 XP is always 3rd level.
Presumably, this is because XP cost differences were used to stagger progression and normalize power levels when classes did not have equivalent power at equivalent levels. If so, then it follows that between 2E and 3E there is some set of changes designed to normalize the relative power of each class so that an equal rate of level progression leads to an equal rate of power progression.
- Is this at least roughly true, or do I misapprehend the situation?
- What changes, more or less, are supposed to have brought the classes' power levels in line?