City of Heroes had a mechanic like that. You could artificially lower your level to match someone else. The benefit to that would be it would erase XP Debt twice as fast ( In CoH if you died you would gain a portion of XP debt so during that time half the XP gained went to the debt and the other half went to leveling progress ). You would have all the powers and slots you had picked out when you were that level so you could play with friends.