There are a few things that Cassandra could have said that might surprise him more, but given that she wants him to command the forces of this Inquisition or whatever it is, he probably shouldn't underestimate what she can come up with.

"Of course -- though you'd still be seeing it with a templar, which makes a difference." He looks at her. "I expect we'd see less of the Carta or the Coterie than you might if you chose a different guide."