I am well aware that it will be much easier that way, but in my opinion it will also be unreasonable. The trap medal is doing a superb job and is a very serious tactical asset. As such it must require some dedication to achieve it. Your way is much easier, I grant that. However, if we all get what we want the easy way, we may as well ask the developers to have the game give us no-loss victories every time and have all medals start at lvl 3 right from the start.
On a side note, I found out something funny. If a bronthor gets trapped or is hit by lightning, his spiked armor comes into play, since he cannot directly counter the attack. If there is no unit nearby, nothing happens. If there is en enemy unit, IT will be hit by the bronthor's armor. The same happens to a friendly unit. It was fun seeing the enemy bronthors get trapped and killing 7 enemy foremen who were right beside the trap