jonesm wrote:
and the damage build is cheaper
Think of it this way, you get what you pay for. So when you pay for cheaper units what are you going to end up with? A lesser quality army.
As to why it is a bad build, it reduces the damage you do the first round (since your damage will not even fire), in a 2 round battle range units do more damage than damage units (4 attack*2 rounds= 8 where damage units would only do 7), you will lose damage units during fights since you do not have enough armor to cover them (resulting in higher maintenance costs), and lastly if you use the "pro" build and go for experienced units you will want only your range to survive so they receive 100% of the experience and it is not wasted on armor or damage units.