As he watched Gump and listened to Briar, he learned at least two things: One, without the little owl, she wouldn't be able to 'see' and Two, she expected to be able to see properly again. He thought the first would be potentially stressful for her, given the owl's vulnerability to harm. It must be a constant concern should an encounter go pear-shaped.
The second was just incredible to even consider possible. Would it be a spell to heal her sight or would she actually acquire new, physical eyes? Wil wasn't going to ask.
“No,” he replied. “I have never seen a witch at work before.” He'd seen the results of a few spells and such, but never the casting or however it was done.