I have been wondering.... Remember earlier in the manga when it was explained that 250000 people or so were sent on a expedition to regain the outer wall? As far as we know they lost and were all eaten. Now, I understand that titans are almost impossible to defeat but how exactly did this work? We are talking about 250000 people here, its a rather large number of people. So.... they really couldn't take the walls back with that effort? I understand titans are basically impossible to fight against under normal conditions but in any scenario it seems weird that the result was just this 250000 people dying and just that.How many titans were there at shiganshina and surrounding areas? We know titans are attracted to people but its not like there are literally swarms of them. The highest number of titans we have seen, and only when specifically called is around 30. So.... You have 250000 completely expendable people fighting, say, hundreds of giants, and you get nothing to show for the expedition at all? Even if there were a couple thousand titans you still outnumbered them by a couple hundred to one. People don't have extremely advanced technology and hardly anyone can even use the 3d gear but under the scenario of expendable people wouldn't there be some form to deal with titans? For the amount of titans we have seen, how long would it take for 250000 people to die? Most titans can't even move at night... How long would it take for titans to eat 250000 people?
So... you have 250000 completely expendable people, a specific time at which titans are consistently useless and with the scouting legion you have a group of people that can consistently kill titans,
even at night. Now, it is kinda up there whether anything they could build to cover the hole in the wall would actually keep titans out but given the circumstances does it not seem like they should have gotten something more out of this than just 250000 people dying? You don't even need to cover both holes to recover the wall, only the one that reyner made. Its a matter of getting the materials to cover the holes to the outer wall and then working at night. Titans are attracted to people so before dawn you'd need to get the people away from the hole so that they don't gather there during the day. Which should be fairly easy to do with horses. Well, maybe my speculation is too optimistic but still... Even traveling at night should be doable with proper mapping and familiarity with the terrain.