Actually I take it back. I see where I went wrong now. Naznatips you are completely correct.
It turns out that the original betas for Starcraft in 96 really WERE using the Warcraft 2 engine but Blizzard completely overhauled it in the Spring/Fall of 97 making it much more than a simple repaint. I knew about the former, but never knew that they had actually rebuilt the thing for Starcraft.
Well argued. ^_^