cinematics - inconsistency in results

How do you guys usually go about making cinematic sequences in the middle or end of a campaign mission?

I tend to remove/pause/hide units that would cause any inconsistency with different runs of the cinematic every time it's played, and create say, the "bad guys" that are going to be attacked at predefined regions, and literally define what unit attacks what, etc. It's all strictly defined. I don't just create units and see that they "battle" consistently everytime.

Weird thing is, in some cases, I get 2 or even 3 different "ways" the battle can turn out. The HP of each unit is the same at the start of the battle, as is the positioning, so I find it really strange that the game engine decides to carry out the cinematic differently every time. Am I just gonna have to tinker away at the triggers until the cinematic comes out the same everytime?

Of course the battle turns out differently each time. Units have variable damage, if i pit 2 footmen against each other, theres no certain way to tell which will come out on top.

The trick is to trigger everything, if you want a certain side to always win, give them overwhelming numbers and reduce the HP of the losing side. Heros should be made immortal and killed via trigger when you want them too.