This detail from Rubens, to the left, was a great example of the center of interest found IN the reflection.
Below is Frank Benson's "Rainy Day". In this painting, the reflection is a design element which enhances the sense of space and piques my curiousity, as well as carrying my eye
through the painting.
The painting at left is a Stanhope Forbes. I love the use of the two, very different, mirrors, especially the rounded mirror in the foreground.
We had a great day. My students dug in, as usual.