intelligence and stealth

[trooper]

One thing I've always been unable to figure out : when you complete an intel project and when it fails (I suppose that occurs when the ennemy has more points available in counter intelligence projects than the points spent in the attacks he has to face during the turn ) does the ennemy always known that an attack has occured, and who launched it (whatever the intel project type). Same question if the project succeed (communication taps, sabotage...) ?