Trial of Iron wasn't made for a first, or even a second playthrough. It was made for those kinds of people who play a game over and over again until they know the game inside and out to give them an official challenge, since there's a not too insignificant number of people who do that with games anyway. It's for the absolutely masochistic gamers who enjoy memorizing an entire game and then flawlessly executing delicately laid plans. I fully expect the percentage of people who get the achievement on Steam will be less than one percent.