I never questioned this because it made a certain amount of balance sense to me, but given that AD troops aren't announced, it did seem sort of out of place.
So I just looked up the rules for TO, and under hidden deployment, there's no mention of announcing the presence of hidden models:
Hidden Deployment. It allows the same type of deployment as CH: L-2 Camouflage, but there is no need to make use of a Marker. Provided that he does not move, the figure with CH: TO Camouflage will remain completely invisible. The player must take note of his figure’s position in the most detailed possible way (Cover, Prone, etc.) so that the adversary will be able to verify the data in the moment in which he reveals his position. If the miniature moves, the player must place a TO Camouflage Marker, and show his adversary that he really was in that position from the beginning of the battle. If the figure performs any other action, he will have to be replaced by the miniature instead of the Marker.
A miniature in Hidden Deployment does not add his Order to the Orders Reserve, as he is not on the game table. However, to carry out his first Order, which reveals his presence on the battlefield, he will not receive the Order from the Orders Reserve but will have to spend his own.
So, long post short: I'm assuming that you don't actually have to announce these models, and that the person who taught me to play (and by extension, my entire play group) has been playing it wrong. Is that correct?
