a) Is this possible?! I mean, the damn map is full of them!

b) Do you mean that you must end your movement on such a place? So,it's almost matter of luck?

c)Let's say I put my troops in a forest,near a road.How do I ambush? I should keep an eye and attack the enemy that passes or is it automatic-like showing a window whenever there is the chance of ambushing?

d) Hmm...how useful is it? I mean, I have tons of armies all over my land, should I waste one of mine by leaving it somewhere for several turns expecting for someone to pass?