The system doesn't encourage power leveling, it encourages community assistance. Power leveling has not ever been a serious problem because the people who power level do so to play with the people they are power leveling. This system isn't going to lead to a mass of noobs trying to infect your game play experience.

Odds are the "Power Leveling" you people are referring to will not be significantly faster than standard partying due to something like loss of chain or lack of links.