The Aztecs saw a good husband like a burning torch leaving no smoke. Such a requirement cannot go hand in hand with a fire which is burning on fresh boughs. The wood must be dry.

The 'smoking mirror', Tezcatlipoca, is the opposite of Quetzalcoatl (the blue-green quetzal serpent).

The bright colours are gone when Quetzalcoatl has left and Tezcatlipoca taken over. Smoke it is because he has only the green spring boughs to make fire of. Mirror it is because sun is not moving higher but sinking lower - a mirror image of ascending.

The twin brothers are the twin aspects of the sun, ascending and descending.