AI and following scripts

[TwoBits]

I've also heard that unit placement can sometimes affect following scripts.

Of course, range will always be an issue for many spells, but I think I remember hearing that for some battlefield spells, such as Flaming Arrows, the casting unit needs to be able to "see" the enemy? And that if you place the casting unit towards your rear, it'll be much less likely to cast than if it was farther forward?

If this is so, I hope some more experienced players can chime in on this, and give some details on the mechanics of how placement can affect scripting (or at least confirm or deny it), outside of obvious range issues.