I agree with PC (Hope you do not mind me shortening your name). They have simply matured, especially Greg since the early seasons. There were many instances this season where they worked together and got along perfectly fine. Plus they are more on equal ground now than way back when. Greg was a lab rat and Nick got to tease him due to that. Now they are both CSI level 3's and in the Season 10 opener, Greg just simply expressed at being frustrated for not really being treated like he was a level 3 but he got over it. (Too soon I still say. I would have loved to have seen him pissed off a bit longer. :lol But as for him and Nick they worked a lot together this season and had no problems between them.