well i see your point, but to manage those sheer numbers takes some skill, you have to scout your enemy, find weak spots in his defenses, find out whens the best time to expand, or where to expand, or if he is expanding, or whatever else there is. All im saying is that any SC player will agree with you that SC uses lots of units, and the higher food limit shows that. But it takes skill to know where to put them. Or on the other hand it takes skill to know how to counter it.
For example:
some one tried a archon rush(12), and attacked me, i got a templar and psi stormed them twice, it killed most of them, all that remained was 2 archons. I had a photon cannon and a goon, i walked around the cannon, and he slowly lost health till they were dead. if i hadn't of done that i wouldn't of had that out post anymore, and its that were the final battle took palce and i won. So SC isn't "just" abut numbers.
