Hmm... I was thinking about this all last night, and I think Jack leaving would have been even more poignant if they had skipped the "Six Months Later" and done it at the end of Day 5 or "A few days later". If he ditched out on Gwen and Rhys while the country was in the middle of riots and political upheaval, and Gwen was sobbing and begging him to stay and help them explain and help them fix things? Whew, now THAT would have been a betrayal.