@tallon1982: What's the source of that information (other than the DA wiki that can be edited by anyone and has in the past claimed a number of absurd things including that if Harrowmont was king with golems, he made Bhelen a golem)? This is a codex:
As well, Denerim was the birthplace of Andraste. One of them, anyway, as several other sites claim to have been the prophet's early home, including Jader, in Orlais. The Chantry takes no stance on which site's claim is valid, but it is well known that Andraste was Fereldan by birth. When visiting the pilgrimage site in Denerim, it is inadvisable to mention Jader at all. -- --From In Pursuit of Knowledge: The Travels of A Chantry Scholar, by Brother Genitivi
It's a given that they broke free from the Chantry. Whether they stay that way is another issue, but the revolution began with Anders. His actions changed everything for mages, forever.
I'm not saying it's impossible they'll lose, but I doubt Cassandra would bother questioning Varric if the Chantry's chances of success were certain, especially since they also lost their Templars. It doesn't seem like Varric thinks they'll get the Circles back. Cassandra also explains she wants the Champion to talk the mages down from having broken free from the Chantry because he was there at the beginning (at least for an apostate Hawke who sided with the Circle of Kirkwall).
If Anders incites a revolution and then they lose and things go back to the way they were before (but with more templar oversight) then that's not changing anything forever. It's a temporary change.
It is FAR too early to say that Anders freed the mages. If they win, you can say that. You can speculate that they will win. But they have not, at this point, won. It may go either way at this piont hence Cassandra's concern or she might even think that the mages will win but it still hasn't happened yet.
One word. Morrigan. In the end if you didn't do the DR in Origins she ended up in Orlais at the right hand of Celene. If you did, she was crossing the Frostbacks in that direction. Ok two words, Flemeth too. Since you as hawke apparently carried her with you in preparation for the warden killing her (omg how wierd was that by the way??)
How common knowledge would that be, though? Leliana might or might not be aware but Cassandra certainly seemed to have no clue.
Alistair was a Templar, lest we forget.
And Thrask. And Keran. Even Cullen, really, once he calms down from his post-torture frenzy in DA2.