It doesn't make sense at all, in anyway anything that happened in this episode. First of all, why would locke do anything that he has done in this episode. Locke is inquisitive more than irrational, he doesn't take dumb actions out of curiosity, he feeds his curiosity by asking questions getting answers. After he gets his answer or at least minimize the doubts he starts acting in his own accord yes. The second thing is why would he press 77 when it clearly says something along the lines of "if the hostiles take control of the station enter 77". Say the station didn't blow up then the closest thing to a reasonable thing any person with 2 braincells would think of is the fact that in this case they are the hostiles and this would alarm "the others". The flashbacks also make no sense and felt more like filler.
Review of Enter 77
