Direct Fire/Assault Questions

[Bacillus98]

Good stuff in this thread. Aetius, for your terrain fire calculation, how did you know that an elevation change from 200 to 600m gives twice the elevation modifier (25%*2=50%) yet 300 to 600m apparently gives a 25% modifier. I don't really follow the rules on elevation modifier portion that discusses "elevation increments". Increments of "how many meters" is where I am confused on (how do you know what the increment value is, 10 m, 100m??