They weren't counting on the Cardassian military to fight off the Allied fleet, though. The Jem'Hadar were going to do that, by themselves at first. The Breen commander had to convince her to let them stand beside the Jem'Hadar. The only contribution by the Cardassians were the unmanned weapons platforms.
I don't remember that?? And they were contributing ships as well as the weapons platforms..
From the memory Alpha:
"In the midst of battle, the Defiant is taking heavy fire. As a Breen warship fires on her, it is suddenly destroyed by a Cardassians ship. They have turned on the Dominion for the destruction of Lakarian City, and begin attacking the Breen and Jem'Hadar."
If they weren't counting on the Cardassians support, why was it the battle turned in the Federations favour once the Cardassian fleet defected?
That response doesn't make sense to me in the context of the episode i just watched last night..