wilderness - 12:56 pm on Nov 5, 2012 (gmt 0)

g1smd,
The use is still redundant in this instance.
Obviously the refer is not blank, it contains a domain name.

FWIW, the solitary use of that line in my very large htaccess in within the image-hot-link section, which results in a denial (not a rewrite or redirect), with specific domain exceptions by use of leading-!