Ender and Bean were given totally new scenarios each time, though, and all their techniques were for attack, not defense. They won because they could adapt to the current circumstances faster and better than the enemy could. This is not the same thing at all as prepping your code so it can be modified easily later. Code preparation requires that you have some idea of what's coming, whereas Ender and Bean had no idea. That's what made Ender so special. He could beat scenarios that had no previous frame of reference.