This episode proves....once again that Abby and Luka make an excellent couple. He was needed in Darfur, but he could easily tell that Abby did not want him to go, so he didn't. He didn't let down his commitment, though, he sent Pratt. I'm actually glad that he sent Pratt, because Pratt deserves it. He was a jackass.
Once again I have to say that I love Luka and Abby together, and I hope eventually they will get married or something. They are perfect together and you can easily tell that Luka is so over Sam and she isn't over him.. Well who's fault is that for not wanting kids.
Luka and Abby...you guys rock!