Flamers can cause multiple hits. I just didn't know (and am not sure if it's true) that you can have multiple "set alight" statuses on an enemy. If you can, that totally explains my base defense wins.
Whoosh! Whoosh! Arrrrggghhhh! Dead next turn..... Regardless of armour, even if the incendiary damage did little. At worst, the morale hit will panic them, at best, they're toast.