Add more comments to the router selection function
Add more comments to the router selection function

Reviewed-By: Wesley Hertlein <ca32100e9f664971b15d1470ddc7f009d907efd3@morganstanley.com>

stdweird/aquilon,guillaume-philippon/aquilon,quattor/aquilon,quattor/aquilon,guillaume-philippon/aquilon,stdweird/aquilon,stdweird/aquilon,guillaume-philippon/aquilon,quattor/aquilon