Well Charles, that also depends on how you move. Move just 1 hex per turn with infantry and your sneaking. Move more than 1 hex and you're not. Your chances of getting spotted rise drastically. And you do have to sneak all the way to your target, at least the part that MAY be under enemy observation. Get spotted once along the way and you'll stay spotted.
Oh yeah, I kind of forgot about that, but it seems in thick woods (realizing now this is the wrong thread) that they always react even if it is just a move of one hex. Maybe I just haven't been enough in that specific situation to know the precise deal in this version yet.
No, sorry, I think that was for this thread, as I wasn't talking to PatG in that one, and though it's related I couldn't find anything that it looked like I was responding to there. I was repsonding to PatG's last response here it would appear.