This is not going to change or fix any problems, this is only going to penalize the casual players that are mostly just hanging out with friends. In fact, this kind of thing is one of the very reasons my wife and I quit EQ2.Experience bonuses or penalties for rating offset between the player and monster now use the highest rated member of the group instead of each group member's rating, to a maximum of 120. This means, among other things, if the highest rated member of the group gets no experience for a monster, nobody in the group will.
My wife and I are both level 100, and all the folks we play with will not be affected. However, we do like to help new folks, and it is quite reasonable to assume that sometime in the future some old friends may join us here. If we cannot team and hang out then that reduces the attraction to the game. And if it weren't for the people that I hang out with then I could be playing any number of single player games, and save the monthly fee.
The part that really makes me grit my teeth is that this change fixes nothing, and is somewhat typical of AE. It is a 'fix' with the best intentions, but without the propper understanding. This will not stop the powerleveling, and this will not stop uber-peds, and frankly I don't think it will slow either of those down. Or have I missed the point, and this is to fix some other thing?
I am not saying AE sucks, on the contrary, I have a lot of respect for their dedication and for all the hard work. Horizons has a lot going for it, and I love the game. I do think that the folks making decisions like this have missed the boat somewhere, though, just like they did when they let multi-classing get so out of hand. And yet, that multi-classing thing has kept a lot of folks here, playing and having a good time. So how bad can it be?
If you see a problem then by all means fix it. Just please make sure the fix does what you intend, and that the net effect is not a reduction in fun. Less fun always translates to fewer players somewhere along the way.
And then you must ask the question, of all the things out there, what made this fix so important? Why were the resources not spent on other things? Again, not an attack but actual questions. As a player I do not see what problem this solves, but I do see a lot of other unsolved problems out there.