I doubt that their intent was to punish playing with friends/guildies, but to encourage players to use the dungeon finder tool more to reduce the time in the queues.
And honestly, I don't understand what difference does it make if heroics get "nerfed". First of all, raids won't get nerfed (which are the main PvE content imo). And you already complain that they are too easy, so does it really matter if they make them even more easy? It's not that big a "nerf" (or a buff, whichever floats your boat) after all. Secondly, I personally tend to meet a lot of 5k dps people, so for me the "nerf" is more than welcome. In addition, there are already people that do the heroics for valor points only, so in the end this "huge nerf to PvE" is pretty meaningless.