That was definitely a tough call. I wasn't sure how the episode was going to end. I'm not sure the Union rules about time travel are all that well thought out. I mean, obviously if you got stuck back in time and used your knowledge of the future to radically change things, that would be bad. But, even if you followed the rules to the letter as Gordon did for the first 3 years, every fruit you eat, animal you kill, tree you chop down for firewood, etc. all impact the world in some way that can ripple forward. I'm not sure that Gordon was wrong to just try to quietly slip into society and live out a normal, low-impact life. I would have liked to see the show spend a little more time rolling around in the messy parts of the decision, both before they went back for 1 month stranded Gordon as well as after. From the "preserving the future we know" aspect, I think in the end that Ed would have had to make the same decision, but I feel like younger Gordon accepted the news a little too easily. Once they told him what had happened and the future that he lost, I think Gordon would have been more a lot more conflicted, even if he ultimately agreed that it was the right thing to do.