It was implimented in CoHO and was one of the most underused abilities in the entire game. Even with command tree upgrades improving the # of dummies, reducing the price and time needed for them to drop in, price drops, and the ability to explode when fired on or when they hit the ground (stun effect, no damage whatsoever), it was a woefull waste of 50mp. Id rather reinforce 2 riflemen to a squad then use that useless crap.
i was one of the few people who fully upgraded it and then i made like the only post for it.
Basically IFFFFF the dummies exploded all weapon system broke in that area for like 5 seconds (awesome time to push),and then a little while longer acc dropped.