Battlefield size in Heroes 5.

I've had many situations where I needed exactly 7 stacks of dragons, or dendroids, or griffins.
Even if it's only needed once in 10 battles, I want to have that option, especially since I can easily create 7 archers...
Here's an example. 7 stacks of 20 archers. And you only have griffins. If you divide the griffins into 7 stacks, you'll win without losses, but if not (and Nival believes that's not possible), you'll lose valuable units. Is that normal?:eek:
It's absurd...