as in response to the person stating that you can try to do a "check" and "balance" on power output vs xp gain.. it also hard....
For instance.. I was group with a bunch of people who needed a healer.. I have a healer and group with them.. I may have use my power 1 to 2 times per battle (well organize group) but gaining a bunch of exp...
there are always "instances" that may be hard to track who is powerleveling and who is not... to sift the whole database and check what zone, what char, what location, what powers etc etc is a tedious task to do
more than likely.. they (the devs) might just put a limit distant for exp gain (like 100 feet) or something worst.