I have been playing R:TW for about two weeks now, and am slowly getting to grips with it (was a M:TW player for quite awhile). So far, I am having moderate success as the Julii, but there is something I haven't been able to figure out. I tried looking in the manual, but couldn't find it...

How does line of sight work? As far as I have understood it, every unit (diplomat, spy, assassin, army) has a sight radius, a radius around it in which terrain, units, cities, bridges etc are revealed. Obviously, this is influenced by terrain (can't see over mountains), and, for spies, seems gets larger the higher the skill of the spy (I seem to recall reading this in the manual).

Now, easy one first, what determines sight radius for armies, diplomats and assassins? Is it experience (in case of an army, command stars)? I seem to recall that there are retinues for generals which increase sight radius, or am I wrong?

Slightly more tricky: Within the sight radius of a unit (taking into account mountains etc), does one always see everything ? My playing experience would suggest no, I have frequently run across encamped armies which I would have thought had been inside my sight radius, but which I didn't see until I was right on top of them - am I missing something? Does the sight radius only apply to landmarks and cities, but not necessarily to units? What determines whether or not I can see an army?

In one of the R:TW guides on the Org (I think it might have been Frogbeastegg's, which is amazing by the way! ) it was mentioned that you should always scout ahead of your main army with a spy (or two) to avoid ambushing armies. Correct me if I'm wrong, but it seems to me that my armies' sight radius is bigger than all but my best spies, so there is little point scouting ahead... or is there? Do spies have a better chance to spot enemy armies?

Related: what about spotting enemy spies/assassins on the map? Does the chance of spotting them depend on the distance from where you're looking (ie how far away from the enemy spy/assassin are you), his experience, your experience...?

Lastly, a question on strategy - how much do you use spies to scout out enemy territory? I used to do it in a very limited fashion, and often only had diplomats in enemy territory - but diplomats have a pathetic sight radius, and, unlike spies, can't really determine army composition. So now I've started sending my spies into enemy territory to find out "what's out there" (yes, I'm one of those players who needs to have as much map info as possible, who looks at a map region covered by the fog of war and starts worrying how many armies could be hidden there!). I'm just wondering if I'm overdoing it (especially since mass spies are expensive!), please share your thoughts...

Any help is appreciated!