Informative! But why do squads occassionally get surpressed on red cover? I don't think I've ever witnessed that in the live game.
You would hope that in a live game, no one would stand on red cover for that long
But as a general rule, red cover increases received accuracy, damage, and received suppression (by about 25%, I think). I believe that all bullets have a suppression value, however tiny. You'd only notice when a modifier is involved, such as the target squad already being suppressed, or standing on red cover for too long (and not dying first).
I remember in vCOH, volksgrenadiers would fire at exactly the same time on the first volley, often causing the target to be temporarily suppressed.