Caliper placement

[retroman_imp]

As I was walking to my bike in the parking lot for some reason (possibly the red Brembos on the first car) I noticed that some calipers were mounted on the front whereas others in the rear of the disc. it was consistently either front-front or rear-rear and one SUV had rear-front placement. Which lead me to wonder as to why and what might be the ideal position or placement for effective braking? On the bikes it's back and front possibly due to mount point constraints..

Just wondering and thought I'd share..

BTW, agree with you all and love riding in this cold weather.