From all the videos i've seen, brute force is definitely used over flanks\strategies, etc. In fact, I don't think flanking would help in the scenarios given...
I seriously hope this game isn't being dumbed down to a game of big explosions targeted to your average Halo fan... Explosions keep idiots around for only so long and by dumbing the game down, the real target of this RTS is pretty much no one.
I don't think I can name a flank in the game thats useful except maybe a sniper flank, but infantry units are to slow for a successful flank.
Their isn't a rock\paper\scissors aspect either... Tank beats lighter vehicles, vehicles beat infantry, infantry beat weaker infantry..
Someone convince me otherwise...